It’s not a crooked deal. It’s certainly undemocratic, but the Colorado rules were very well known long ago, and those insider rules were followed. Had Trump played by those rules, instead of ignoring the state, he could have done quite well.
Trump could have “done well”? While the Colorado GOP is tweeting Never Trump? Yeah, right. LOL.
Trump could have turned on the charm and made an effort to connect with the Colorado GOP establishment. There are certainly party leaders who hate/fear him, but there are just as certainly party leaders who could be seduced by a billionaire who tried.
He never made the case to them that their self-interest would be served by giving him a proportionate share of the delegates based on his popularity in the state, and that is an easy case to make if you have money on your side. I'm not quite saying bribery, not any more than a man who takes a woman out for an extravagant evening is paying for a particular outcome, but an implicit appeal to their greed would likely have done it.