Hi,
There is a particularly nasty disease ( IBD ) boa's can carry without symptoms for a long time ( possibly even their whole lives ) that will kill your ball pythons in a couple of weeks.
Skipping quarantine if you are mixing in boas with BP's is just plain risky.
And when dealing with animals in quarantine it is important not to share any equipment and to always take care of your established collection before going near the quarantine area.
The idea being to make sure you reduce the chances of anything being transfered from the new animals to your established collection.
I have no idea how widespread IBD really is so I can't help you evaluate the risk.
Possibly some of the bigger boa guys might be able to help but I don't know how much work has really been done to find out.
dr del