Do you have an extra small QT, that you could pack with live rock? When I was in your shoes, I didn’t even bother treating my dragonet until the very end of my fallow period. I set-up a 20g QT just for her, and packed it with rock and a few bottles of pods. And just focused on keeping her eating and alive.
For the last 14 days, I pulled the rock and added the CP, then transferred her right to my DT. I can’t really say it was the best idea not to observe her after treatment... but it was the best I could come up with to keep her alive at the time.