Yes, there could be some blowback.
I will say that Donald doesn't come across as the complaining type. First, he was specifically asked about offensive holding. His answer was more on the sincere side than on the complaining side. Nor does he come across as the "conspiracy theory" type.
Also, I don't see any coach that outdoes McVay in the "respect the refs", "control what only you can control" category, unless it's Frank Reich of the Colts. Did you see the end of the Colts Packers game? Five consecutive holding calls to prevent the Colts from salting it away with a field goal in regulation? In a year where total holding calls are down? One of which was obvious, one sort of okay, and three less than what Donald reportedly gets on every play?
Yet the Colts still won in overtime. And we won too!
I hope the Rams meet the Colts in the Super Bowl, and that both McVay and Reich show their good sportsmanship. My two laws of sportsmanship are:
1. It's only a game,
2. Games reflect life, and life is important, so you should play to win.
If one complains too much about the refs, it is a violation point 1. Did Donald do that? If he did, I trust McVay will get on his case.
That all said, how can anyone doubt that "something is rotten in the 'sport' of Denmark"?