Even if you somehow encounter a similar mixer, the chances are very high that your are going to get scammed by them. Chipmixer had years of experience and reputation. A random mixer will never have the same amount of trust unless it proves itself first. And even though all the reputation CM had, people still discuss if CM were logging their users or not because of the 7tb seized data by the FBI. Are you going to trust another crypto mixer so blindly after what happened?
No doubt chipmixer was trustable and it was providing the best mixing services for so long until seized by the authorities. Right now people are missing the services of chip mixers, even though there are many mixers services out there.
That's why you say that it's a group of mixers, that's a bit worrying because you don't know that it's a group of scammers just trying to bite you with nice words, so be careful, friend.
For sure, we should not trust any mixing service blindly as many are popping up after the chipmixer closure. I would not use any service unless and until I have some good feedback about it.
If you use it more than once, it is possible you receive your own coins again.
It does not matter if we receive our own coins back as there is no one's name written on any coin. The main purpose is to mix the coins so that the coin we received is not traceable.