On Celebrity Apprentice, Trump often says he will match the donation to whatever cause. Of course, it probably isn’t coming out of his personal pocket. Probably some layer of his Trump Empire. I don’t know if he ever did it with the Vet charities that were played for but I do know he has done it multiple times every season.
Whenever money comes out of someones business as a donation, it is still coming from them, just pre tax is all.