I think I've only ever seen this happen in
Shin no Nakama ...and that character left the party after the protagonist was kicked out.
In this one, the situation is wildly different.
There was one schemer with very corrupt intentions who got him to leave more or less by himself.
And two major companions who trusted him, though only one had enough freedom to leave right away.
Here the situation is more or less reversed as he was kicked out by the majority of the party while the one companion who trusts him cannot leave, for now at least. And apparently this one companion had enough authority to keep the MC in the party so the firing had to happen while she was absent. There are inconsistencies there, but basically it's a whole party of cretins who thought they could do well enough without the MC instead of one schemer.
There are a few other stories where the banished character is actually followed by one or more other party members, immediately or after a short delay. Pretty uncommon, but not rare enough that it's exactly original at this point.