First off the dude is excellent, 32 goals in 40 games or so. Secondly and most importantly, he is owned by Doyen Sports, the same spors investment company that is one of the partners and backers of the thai dude who just bought 48%. So basically him coming means they really wont have to pay this fee fully, its like this company will pay itself to get their own player to Milan most likely
Same reason they are linked with Kondogbia, this company's commodity.