use a bucket dehumidifier in the tent or next to the air intake. inside the tent will work better. might work on a short term basis. messier than a proper dehumidifier but should drop it enough in a small space to keep it from getting too high

https://www.amazon.com/Camco-44282-Fragrance-Moisture-Absorber/dp/B078Y2TVN2/ref=sr_1_7?crid=OSHMFTD4HQQG&keywords=bucket+dehumidifier&qid=1690982090&sprefix=bucket+dehumidifier%2Caps%2C181&sr=8-7

this is just one example you might have a local favorite, boats use these to keep the mold down should work in a tent