I have a normal larder fridge i hang my roe in and dont have a fan. Have not had any issues with mould or anything else and that is with a roe in for up to 2 weeks. I do open the fridge every few days to just check all is fine but other than that I just leave it to its own devices. Have had 2 fit in comfortably for around 10 days and no issues.
A fridge doesn't have a fan where as a chiller does. Not sure if that is any help? Obviously, a chiller will get your carcass down in temperature much quicker than a fridge but it's not going to make much difference on small deer!