Your temps are definitely not too low, and as stated in the previous post, the day-time highs may be a little too high. However, there are probably as many cases of RI caused by sub-optimal humidity with tropical boids as are caused by sub-optimal temps. Initial sneezing is many times caused by irritated lung tissue and not necessarily an actual RI, and can usually be eliminated by correcting the environmental conditions within the enclosure. This is if the condition is caught before it has advanced into a full RI.

Kelly