Same argument that the ‘centrists’ used when they just didn’t vote in any of the elections that brought us to this point.
Has he made any policy, voted along lines that supported them, or done anything that indicates he’s pushing their agenda?
If the answer is no, and you’d rather him just not have a chance at winning when he’s only shown he’s a genuinely good representative, then you’re the problem… not him taking money for something he’s giving nothing in return for.
Don’t worry, they’ll just give the Mustard Mussolini the first Mercedes-Benz Peace Prize and get an exception.