With regards marksmanship I wonder sometimes about the trend for kipplaufs, especially in reasonably pokey calibres such as those mentioned. A 5.5lb unmoderated (presumably) rifle in 7x65 might be the reserve of a very good/confident rifleman, they won’t help flinching and certainly not seeing shot reaction. Lovely little things no doubt but not what I’d choose for everyday deer management.
7mm's pokey? have you tried DG/big game calibres? Muir's girlfriend eat's 7mm rifles for breakfast
I think this could all be summarised with:
a. visitors should have tried/practised before the outing off sticks and with the rifles they used/borrowed
b. thought should have been given into the bullet selection in regards of shot placement and the visitors should have been aware of this (ie. don't lung shoot a deer with a barnes monolithic for example)
c. clarity on shot placement expectations, better rules on game standing broadside perhaps and agreeding on bullet placement say, through shoulders
d. booze was mentioned, that's fun and great, but a recipe for disaster both from ethical shooting perspectives, and risk of accidents
Regarding thermal - not my thing really, don't blame the OP for not having one.
Regarding dogs - nice to have, not a 'must', if your tracking skills are excellent, you can recover almost anything. That said, if you can't, then don't leave it, either fetch your trained dog from wherever it is, or call a tracking service - don't leave the deer thinking you just couldn't find it or it 'probably will be ok with 3 legs as they're tough buggers and all that' - ethics and morals come in here, but also public perception of our sport if walkers/locals see/find wounded deer.
OP probably has realised by now how his next outing with visitors can be improved on, and that's fine, we're not all pro's from day 1, and there's nothing wrong with being open and honest about bad experiences, what's important is taking feedback and one's own lessons' and imbedding them into future practises.