Since you asked there are several grammar and expression errors such as:
“…who thinks he brings a misfortune whenever he is…” I think you meant wherever (unless this is a time travel story) he is and should be; ‘…who thinks he brings misfortune wherever he is…’.

“…becomes a member of a group with super-powered people…” should read; ‘…a group of super powered people…’ I would suggest changing it further to ‘…a group of super heroes…’.

“…he starts thinking that this is turnaround in his life…” should read; ‘…he thinks this is a turning point in his life…’

sentence construct appears flawed as well, for example the first sentence contains too many clauses and needs to be split in to two separate sentences. The first should describe his character and the second what he does.

However, from a concept perspective the logline as whole fails to describe a clear enough character (despite its many words) and lacks appropriate flaws and motivations. The entire first sentence is redundant and could be replaced with shorter descriptions.

Richiev’s re draft is much better but lacks a definition of the group he joins. Perhaps instead of naming the group best to describe them i.e:

When the leader of a super hero group is killed, its newest member, a former homeless man with the power to (Whatever his power is) must (Do this thing) if he?s to save his team.

Hope this helps.

“…his split-personality breaks him out of prison, and when he arrives in a new city, he finds a house and falls in love with it…”

This is a series of events part of a sequence and not a single significant event that occurs out of the ordinary which changes the life of the MC in manner that motivates him to need a specific goal.

Secondly the inciting incident normally needs to happen to the MC without their control. If the MC did the inciting incident to him self, in the way you are suggesting, then it would have happened regardless and there fore is not an unusual event.