My current read on the situation is that this is essentially an internal coup within Maduro's own party and military against him, and Trump is happy to take credit for it, and they are happy to give it to him so they aren't seen as traitors by the remaining maduro loyalists. Most likely they will talk up their end and demand Maduro back, only to be tried and executed there. They will go from being as corrupt as Venezuela to merely being as corrupt as India, and Trump will parade this as a massive win and claim Venezuela is great again.

I'd guess this was on the table for a while, but previous neocons didn't want to cut this deal with members of Maduro's regime, instead looking to back the opposition liberal side, but Trump is desperate for a win right now so he went with the deal on the table.