The high heat can cause dramatic stretch and airy fluffy flower. Can you get an exhaust fan in their or draw in cold air from outside into your grow? I like to run my RH around 40 to 50% through most of flower and temps between 75 and 80 night time and lights on temps. I drop temps and RH in late flower for last 2 weeks I run my RH at around 30% and the temps between 65 and 75 F. You will get better resin production and terp profiles if you can do this IMO. I wouldnt let the grow get much above 85 F if you can help it heat stress can definitely hermie plants and throw nanners some plants handle the heat better and high RH most sativas are good for that Indicas don't like heat and high RH you will have issues with bud rot and mold. I have a 6 inch inline fan with speed adjust in my 2x4x5 cab and I can control the heat and RH pretty good with just that but I do also have to use a dehumidifier and humidifier depending on the season.