He knew this when the other windows were open. Why did he wait until his only option was the desert? Why not make sacrifices to go to a better league?
He has a contract and wanted the club to honor it. I think when the window closed he expected he'd have chances to play here and there...but it became clear to him that Benitez was serious about freezing him out. But that's my speculating based on an out of shape Rondon starting, while Benitez criticized James' fitness.
I think the real impetus was outreach from the Colombian FA - they told him he could return and even gave the olive branch of giving advanced notice to Everton that he might be included in the Oct call ups...on the condition he get some minutes. That he agreed to this 72 hours after that conversation with his NT coach seems too coincidental after he had turned down a similar opp to play in Istanbul just a couple weeks earlier.