I'm thinking that my head hurts thinking about it!

Too much turkey and vino perhaps.
Population dynamics and BT deer movement during the rut is dicey stuff to consider - Researchers have spent very little (none?) time on it . I gave up looking for studies on BTs and rutting behaviors quite awhile back. There is one good article on JSTOR, a Journal of Mammology study on BT population dynamics. I think it was based in the Trinity Alps, though I'm not sure on that, but that study had nothing to do with the rut. I found that if I wanted to understand deer movement issues during the rut, I had to study WTs, since there is literally mountains of studies on that species. I had to accept that though the species are not identical, they share enough similar behaviors that I could then infer what was happening, or what I was seeing in the BT world. I think that is where you might want to spend some time too. Googling "scholarly articles for" and then whatever phrase you're interested in following that will get you off to a good start.
My thoughts on your scenario, based on my (inferred) understanding of deer movement during the rut, with a couple of blanket statements to start:
1. I'm working from memory and a mental conglomeration of information gained through five or six years of readings on the topic. I believe what I'm writing is correct, though I cannot guarantee it. In some cases, field observations or studies by other researchers may refute what I've accepted as factual. In many cases though, I've already read those research articles or abstracts of studies and accepted or rejected them myself.
2. Every buck is an individual. They have different personalities and are totally unpredictable (as a group) in how they will respond to any given situation. The same individual may respond the same way every time a situation comes up, but it will likely be different from how other animals react to that same situation. For example, some bucks may only participate in a short portion of the entire breeding season, while others may stay active into the winter months.
3. Bucks leave their maternal family and move to a new territory typically during the spring or summer of their first year, though sometimes they may stay with their family into the second year. Young BTs relocate, on average, somewhere around four miles, but as much as twelve or more miles from their birth place. They seem to find an area with a population structure suitable to their liking in an elevation and ecosystem that they prefer. They develop relationships with the older/mature deer in their new homes and fall into the social structure in the lower ranks of dominance.
4. Bucks form bachelor groups in spring or early summer and over the course of several months re-establish dominance rankings amongst themselves, and become familiar with the scent of all the other deer within the local and (likely) closely adjacent herds. Though every buck is an individual, it is generally accepted that they spend the majority of their lives within a square mile area, plus or minus. The deer in that bachelor herd have overlapping but not identical territories. Likely the level of dominance established early on determines which buck gets the best bedding areas, the best core zone areas when they break up, and ultimately, the best breeding areas. The others work the fringes of the intersecting territories or follow the leader as a subordinate.
So given your scenario, I believe that you are correct that the early loss of one of the more dominant bucks may leave some does untended to during an early/first estrus period, and perhaps a resultant perceived reduction in rut activity (from our point of view) in that local area. When we read this forum though, we often accept spikes and small forkies harassing does as rutting activity. I believe that would still be the case in your scenario too, even if no actual breeding takes place, the onset of estrus would have the young bucks acting as expected.
What we don't know is how bucks really travel during the rut. My understanding or interpretation is that once the does really start popping, the bucks will search often well outside their normal territories for hot does. My belief is that the younger bucks likely stay resident and hope for a chance to breed a doe in the absence of a dominant buck. It is likely the 3.5 - 7.5 or 8.5 year old bucks that do a lot of travelling once the does in their own territories are no longer hot. Anywhere they go, they are dominant enough for a doe to accept them as a suitable breeder, though they may still have to compete for that doe in the presence of several mature bucks. Given your scenario, after the initial first estrus and assuming other mature bucks are coming and going from adjacent areas into your drainage, there should be enough buck traffic to serve the needs of your seven mature does by the end of the second estrus. In a situation where there are not enough dominant bucks in the region to serve the needs of all the does, I believe that a persistent year-and-a-half old buck will eventually be allowed to breed a mature doe. She has no other choice.
I'm not sure if that answers your questions, nor whether it is entirely correct. I believe it is correct in general, but perhaps not for each individual doe or buck.
Sidenote: just an observation from Oct. 30th up in Mason. I was working in my privately owned clearcut and found a fresh rub and decided to put a cam on it. I went in and was very noisy removing brush and breaking limbs off the tree I was going to hang the cam on. I placed the cam and walked maybe 25 yards to leave and noticed movement behind me. A doe came straight to where I hung the cam (wrong side - I got no video) and seconds later, I saw that she had a decent, not large, forkie in tow. I watched them head into the bush, attempted to follow them for a few seconds, then eventually turned to leave. I found that they had circled and she headed back out into the cut in order to cross to the other side, the poor buck looking embarrassed that he had no choice but to follow her out into the wide-open space with a human close by. After the fact, I felt like she intentionally came to my noise looking/hoping for a better buck whom she thought was tearing up the place. I'm betting that if a more dominant buck had been there for her, that smaller buck with her would have been out, and the bigger better version in. (Women!)
Sidenote2 - no bucks hit that rub in the next three weeks. Only one buck and several doe came through. Rubbing behavior seems to stop once the rut is on.