“Peter says it is necessary to chose a replacement as was prophesied”
So, Peter made the decision then.
“who the two candidates were was not his decision but probably of all the apostles present”
Probably!= not in scripture.
“it was by lot the replacement was chosen.”
Again, we see Peter starting the whole ball rolling and the Apostles following him.
“So, Peter made the decision then.”
If that’s how you see it then that’s how you see it. But as I read I don’t get the sense of Peter being the head of the church and being deferred to as THE leader.
Respect? Yes! He’s an apostle and older man. A “pillar” as Paul called him as well as James and John? Quite so!