If he was fired because of low ratings (what Murphy has said, FSD has said nothing to my knowledge) I don't think FSD is blaming him for low ratings, but that cost had to be cut because of the lower ratings.
Low ratings = lower ad revenue
Murphy was the only one who was expendable. He carried a larger salary than Elliot, a third studio analyst and guy between the benches isn't needed and with Mickey traveling more a substitute color guy wasn't needed anymore.
Keating, York, Hogan and Thompson work across all FSD broadcasts - not just the Wings - so they carry more value than Murphy. Elliot spent 10 years as an analyst for the Thrashers (and won a couple Emmy's too) and is probably being groomed as Mickey's repacement.
Someone started an online petition, not sure how much weight these things carry but here you go:
http://www.ipetitions.com/petition/get-fox-sports-detroit-to-rehire-larry-murphy/
MisfitJake got a reaction from puckloo39 in Larry Murphy Fired by FSD
MisfitJake got a reaction from wingsgirl001 in Larry Murphy Fired by FSD