this is turning weirder and weirder... I agree with The Truth, I don't want to read too much into this.... But those are pretty unequivocally traced tears running down his cheeks. The fact that they go down from the middle of his eyes gives it away in the reflection (though that screencap you posted didn't really capture them). His eyes look baggier than usual in the interview though.
On a more common-sense take, though, it seems improbable that DJ was JUST done crying when he had a scheduled media appointment, from the comfort of his own home, and didn't even had enough time to wipe away the tears before the camera started rolling. Idk... As far as DeMar being traded, that would be out of left field for sure. Imagine spending weeks on here discussing trade packages for DD pre-draft, only for him to be traded at the start of training camp