Would A Green Laser Sight Show Up On A Thermal Monocular?

Basically, Night Vision is an amplifier of light compared to thermal vision which shows heat gradient (different amounts of heat are translated to different colors or grey levels)

Night vision is like a hearing aid expanding your senses ability to detect what is just beyond sensory ability, while thermal is like a radio receiver - showing your senses what they cannot detect.

+1 to above about designator laser. Those do not impart enough energy to the target to heat it above ambient temperature. No temp difference = no show on thermal.
 
https://www.amazon.com/s?k=two+piece+30mm+mount&ref=nb_sb_noss

30mm tube on Leopold tracker is not long enough to put two piece mount, only one, unfortunately they are not sold as single ring.

depends on your rifle - do you need a "reach back" mount for a comfortable head position?

Ideally if you get good quick release mount, that will give you a chance to use the monocular for spotting and mount it quickly if you going to use it as a sight.

https://www.amazon.com/UTG-2PCs-Grade-Picatinny-Rings/dp/B004HIHQLM/ref=sr_1_15?dchild=1&keywords=quick+release+two+piece+30mm+mount&qid=1605691301&sr=8-15



I would not recommend to use Leopold Tracker on something with a recoil, I am not sure they are designed for that.