Not true.
It has everything to do with this Commissioner's performance on the job and the possible mismanagement which led to his being canned.
True.
There were additional issues with the comissioner, he refused to accept the budget cuts Palin imposed from the Legislature. He was publicly insubordinate and he refused to discipline and control an out of control cop. There were other issues as well, and a long time line, Palin was Mayor when this started and Governor when she invoked the "service at her pleasure" that you correctly concluded she had.
http://www.adn.com/monegan/story/492964.html
WHY PALIN FIRED MONEGAN Monegan was a Palin appointee, and she had a right to fire him for any reason. She's previously refused to say exactly why she got rid of him, but laid out several reasons Wednesday, saying she's decided to talk about it because Monegan is.
Palin said he wasn't doing enough to fill state trooper vacancies and battle alcohol abuse issues. She said he "did not turn out to be a team player on budgeting issues."
Palin said it's fine to have debates during cabinet meetings over the budget but Monegan went further and indicated to legislators she wasn't proposing enough spending. Palin's acting chief of staff, Mike Nizich, said Monegan asked legislators for spending that hadn't been authorized by the governor.