one way...

Try to find a way to let your kid spend more time with his Daddy. Your kid can tell his Daddy that he wants to tag along of one his Chinese trip.

During this long time, the two can have fun and become closer. During this period, your kid just talks about his colllege life, using a causal tone, "My roommate has this and that. But I don't envy them." And then show a sad face.

If Daddy is reasonable, he should pitch in to help. However, if he still does not get it, forget about his Daddy.

Think of this way, at least he paid child support. There is a 閆連山（閻叫獸）did not even do that, plus child abuse. This 閻叫獸 is a famous professor in his domain international.