Hi python, gotta get those temps down, the plants look great for 6 weeks in though. I have a bunch of different tent/cabs and a main flower room. I do different things in them at different cycle times and depending on what I'm doing (different lights, number of plants, size of pots) the rooms can behave differently. I always step back to the basics when I'm having an issue with temps or humidity. Basic rules I use for cooling and humidity control are:
Bring in cooler/drier air - this works the best imo, if you're using passive intake and it doesn't cut it, put an inline or booster fan in or crank it higher (or go bigger)
Exhaust more/faster, same as first one but on your exhaust vent
Increase circulation which has already been mentioned above, sometimes do this with one of the two above.
I'd recommend higher air circulation before defoliation if you can avoid it, I've done some light defoliation with strains that have dense/packed leaves at the end of the cycle but it's usually my last resort and only if I think it may affect/induce mould. Getting the temps down, reducing your humidity and airflow should take care of any potential mould though. Trim off any dead or dying leaves but plucking healthy leaves is best kept to a minimum imo.
Cheers and good luck, not long now...