Barco didn't play last night against Uruguay because as Argentina were already qualified to the next round, it was mostly subs.
In the next round, there are 4 teams, they all play each other, the top two go to the Olympics.
His next matches are against Venezuela on the 5th, Paraguay on the 8th...
I'd be pretty surprised if that's him? As far as I know, he doesn't have Twitter and uses exclusively Instagram. I'd be surprised if for this he decided to randomly not post anything on IG and go to a Twitter account he doesn't use
Boca might be rejecting it because according to reports from here before today they think they can get Barco to agree to renew his contract with a slightly higher release clause. They know he's probably leaving this window anyway, but if he renews he'd leave Boca with a bit more money
While the whole "clubs look at who's Brighton's scouting to sign players" thing is true, in this case Manchester City have been scouting Barco for longer than Brighton has