Here’s a few insights and tips for ya. First off, I commend you for attempting this on your deer hide.
Here goes… I hate to break it to you but vinegar wasn’t a good idea
You started right, Fleshing-good, salting-good, pickling- good but DONT use vinegar. Pickling is used to draw out fats within the skin and to make the skin more tenable for shaving and eventual tanning. Formic acid or citric acid is much better, safer, and you will get a softer leather and won’t leave that sour/vinegar smell. However the biggest and most detrimental step you still need to do is shaving the hide down thinner than what it naturally is. This is different than fleshing. Deer and elk leather is the best rain gear God ever made. It’s thick and built to repel moisture. Shaving the hide down to 1/8” thin allows the tanning product to permeate thoroughly within the hide. Thinning the hide through shaving also makes the hide much easier and pliable/soft. That’s why you hear stories of guys home tanning hides and they get super hard like a board. Pictures of native american women scraping Buffalo hides were the old way this was done. Following fleshing they ‘scraped’ the hide with bone tools that thinned the skin to a much thinner piece before they brain tanned it and then smoke treated the leather. Today the tool commonly used is a shaving wheel.
The vinegar smell won’t leave either, sorry. The good news is you can still salvage it and may be able to get rid of the vinegar smell, if your interested msg me and I can give ya some ideas of that before you tan it
Hope this helped and gave ya some options