I don't think a jump like you're doing is enough to make that gap. You'll need a little more momentum, which you can get by jumping from the left side of the platform instead of the right.
This video (6:30 in) shows you the way I find most consistent to do it. iirc it's way easier with 2 jump buttons (one button for each jump, and don't let go of the first button until after you get the jump).
I'm 99% sure that signal isn't peer to peer. Afaik all messages go through signal's servers, but they're end to end encrypted so the server can't see message contents, or who the messages are coming from.
The only thing that's peer to peer are calls, but you can turn on 'Always relay calls' from settings to relay them through Signal's servers.