Your takeaway is accurate. Since you can't get lower temps, adequate circulation is vital at the RH you're sitting at. That being said, a slightly higher than ideal RH will prevent too rapid of a drying, so you'll retain more
terpenes and allow the natural degradation processes to occur that make for good smoke.
Edit: the above is within reason. If you're sitting at 75F, you're still in an unlikeable position. Worst case, if you have another space that's cooler (an uninsulated garage, etc) then move the plants there. Cooler than 60F is ok, with adequate ventilation, you're just looking at a longer dry time.