You dont need to ask more money to get a commitment to the player, bottom line is that he hasnt done anything to earn more money or demand a place in the first team... but anyway, if he wants more money and a secure place in the first team, then Im glad he is leaving
When you're going to be 21 years old and have 1 year left on your contract, you have every right to ask for a commitment and opportunity.
if you're not willing to give it, move on ---- which I'm sure Juve is more than willing to do because he's just not that good. If he was, they'd give him a pay raise (which would at the bottom of the team) and a spot in the squad.
Let him go for cheap and attach a sell-on clause and hope to make some money down the road off of him. But there's no reason for Hasa to agree to stay with Juventus so he can play for NextGen.
This should be a simple decision and transfer with no hard feelings involved from either side.