A pulsar Telos XP50 handheld thermal monocular ($3k), or pulsar Merger XP50 thermal binoculars ($6k) would probably be the best options for what you are looking for. They aren't cheap, but you will be thankful that you bought the good stuff. You will feel like you OWN THE DARK. If something is out there, you will see it.
Digital night vision, like the spotlights you are using, will "blind you out" in high humidity and foggy conditions. Thermal will see through the fog better. Thermal still struggles in fog, but it's way better than lights or nightvision. Good thermal has better thermal sensitivity (for example NETD <18mK thermal sensitivity of the pulsar telos is about as good as what's available right now.) and will penetrate the fog better. NETD of <40mK can produce great images in dry conditions. But when it gets foggy or misty out, the lower mK will really stand out.
Pulsar axion thermal monoculars are a cheaper option that still give good results. I have an older Axion XQ38LRF, with <40mK sensitivity. On a foggy night i think I can identify an animal about twice as far out with the thermal as I can with my naked eye. Whereas if i turn on a spotlight, I get blinded by the bright fog and can see only about 1/3 as far as I can with my naked eye in the dark with ambient light.