Governors don't get impeached because of bad decisions or their inability to correctly interpret the U.S. Constitution.
Governors get impeached because of gross financial improprieties or corruption that becomes too embarrassing for the party concerned. Although Blagojevich did try to sell Obama's Senate seat after the 2008 election...
This situation, regardless of how vocal the GOP minority in the NM legislature gets, is not gonna rise to the level of impeachment in the Dem controlled house and senate.
No matter how we here feel about the subject (and the good citizens of the state who support the 2A and RKBA), for the ruling party and the majority of voters in the state, Grisham's crap isn't gonna be regarded as "high crimes and misdemeanors" or the other common grounds for impeachment, willful neglect of duty, corruption in office, habitual drunkenness, incompetency, or any offense involving moral turpitude while in office. Even though we can argue that disregarding a state and federal constitution is willful neglect of duty, incompetence, etc., in the current social climate, nah, not gonna happen.
I'd love to be pleasantly surprised, though.