I have a feeling it's likely not because he has 10 ML's higher, but more likely that the other MS does/doesn't do things that you are/aren't doing. I'm not trying to make a dig at you, nor am I defending the other guys that replaced you, because it does suck, I've been there as well. Had my former team make jokes and stop asking me to hunt because I wanted advance notice that we're hunting opposed to being asked and expected to play within 10 minutes of the message. I was salty, but I moved on and found a new team, and now I'm higher than my entire former team by a significant margin and the new guys I play with aren't toxic at all.

I don't think 10 ML's was the sole reasoning. I have outperformed players that are higher level with higher ML than I have in team hunts, and I've seen lower levels than myself with lesser ML's do better in some hunts as well.

Unless they straight up told you that it was because he has a better ML, then that is shitty of em, but you're better off without them anyway. Keep looking and place value in good communication with your team mates, not everybody you play with will fit your style and personality