There are a few reasons this was the wrong move:
1. Perhaps the most important, the plain language of the bylaws actually doesn't give the chair the power to remove an officer for refusing to back the party's presidential nominee. The bylaws state, "The Chairman shall have the power to declare vacant the seat of any officer who refuses to support the Republican nominee for any office within the State of Michigan." The office of President is not an office within the State of Michigan. There's an argument to be made that the chairman should have the power to boot an officer for refusing to support the Republican nominee for any position on the ballot in Michigan, but that's not what the bylaws actually say. For being the party that supports judicial conservatism, interpreting the bylaws any other way is pure hypocrisy.
Even if you want to be pedantic that the office of President is not technically
within the State of Michigan, the office of Elector certainly is. Otherwise, I agree with your post, but making this technicality your most important point is ludicrous.