I think it could be a bit of both, or maybe both entirely.
What I mean is, everything that Bukele has done in El Salvador does not deny gang members traveling to the US, maybe because of his efforts, some upon noticing that the tide was changing might've simply changed branches and moved to LA or elsewhere in the US. Abandoning ship instead of staying and being captured.
Perhaps Bukele would not want to disclose this information outright to not ruffle the feathers of his people, or maybe it is known and no one cares, so long as they do not live in the country and aren't allowed back in. And in fact, in that interview with Tucker, Bukele himself made mention of Spain not deporting one of the gang members they had captured, so if one of the got captured in Europe, it means that dozens must've flown in that direction as well, which means that the US, which is the first destination because it is so close, has to be undergoing a similar process of accepting gang member refugees.
But then, Trump was back on campaign mode and he loves to make such large statements and declarations to appeal to his base, so there might be some fiction mixed in there too.