That's something you will have to decide. Once there is actual fighting, I never put the same two back together.
Caution: If you do let them have playtime together ... Under no circumstances do you leave them unsupervised. Keep a towel, baby blanket or pillowcase handy to throw over them should they start snuffling again. The sudden "being in the dark and covered" usually startles them a little and gives you just enough time to grab one safely. Do not use a full size blanket or a large bath towel ... they may weigh to much. It would be best if there are two people present when/if you let them have playtime together. Just remember it is
playtime and should be enjoyed, not a time to fight and get stressed.
I would prepare a Mini First Aide Kit for Chinchillas and have it where you know where it is and can get your hands on it quickly, should you need it.
I'm going to start a new thread listing what should be in the kit. I would love to see what other people might have or would think would be needed in the kit (I'm sure I've forgotten a few things.)
Jo Ann