I QT for 6 months minimum regardless.
1 month is not long enough QT in my opinion.
Some have claimed that some illnesses have been seen to lie dormant and become active at 9 months. So some vets are starting to advocate 1 year QTs.
QT should be in a totally different area/room as your snake.
Being in the same room defeats the purpose of QT since they are still exposed to each other via airborne nasties. The point is to keep them separate.
You want to use different tools for your QT and your resident animals. For example, using different tongs for feeding to avoid cross contamination.
Work with your resident animals first before handling a QT animal. This is also to avoid cross contamination and risk to your animals.