You miss one small point.
They are voting in Indiana. It is not a “Voterless” state like Colorado.
The outcome in Indiana, whatever it turns out to be is not rigged.
Are you from Colorado? If you or I don't like it (I'm not from CO, and I prefer primary elections, too), we can move there, join the GOP there, and get them to remake the rules. Or fail in the attempt. Right?
Why should we be allowed to run Colorado's delegate selection from New York or Ohio or Washington, D.C.? It's their state, isn't it? Conservatives accept eccentric differences among the States. Don't we?