I hate to bring this up because the forum goes nuts for a month or more every time.
There is a chance of cryptosporidium in those snakes. Do not share any utensils, cages, or decor with the other snakes in your collection until you're sure they're crypto free. Soak their stuff in a mild bleach solution before re-use with other snakes.
Then: keep the temp at a pretty constant 80 degrees, measure this with something better than a turkey probe and give the affected snakes 3-5 days to recover from barfing. Feed them a reasonable meal that you're sure is thawed (feel it) and take it from there.
Meanwhile: collect fecal material from each snake as it becomes available. Collect it continuously and store it individually in ziplock bags, at room temp, away from the other snakes.
If the snakes continue to barf, contact me and I'll connect you to a vet that can take mailed in samples or you can contact your local exotic vet for testing. It's fairly inexpensive insurance.
Wash your hands between cages, handle the suspect snakes last and double check the temps. Jeff Hardwick Jis97@aol.com