Do we have a proof that Yeon actually died?

Yeah in the last/second last episode of season 1 vince had gone to visit yoen's grave. He himself said that.

But that’s just his gravestone right.. what if it was yeon’s brother who died & what if Yeon is living somewhere else with his brothers identity, I mean his parents always wanted that right..just saying ╮(￣▽￣)╭