No party is immune from patronage appointments. In fact, parties need to be seen to be giving a few favors as to entice volunteers and donations.
In this particular case, I would not be surprised that a cross-party deal was reached. Biden Jr. got an Amtrak appointment (which he had not earned) in exchange for a political hack from the Republican side getting an appointment he/she did not deserve either.
We need a new system of governance: one without political parties and the favors that discredit the whole system.