In the interim, try moving the dehumidifier into the grow tent and vent to grow tent to the garage space instead of the front office. That should help some.
It looks to me like you’re adding CO2 (based on the line drops near your fans). In that case, I’d vent the tent only as much as necessary to keep temperatures from rising; unfortunately, the dehumidifier will add heat…
Hope I didn’t throw too much at you with the HRV info. I think it’s worth looking at, even if you need to put it off for now. Climate control is going to be a large chunk of your overhead.