Tawnos
A guy with a bass
Because he's not recognizable like Emerick and NBC has prioritized that and/or being a former player pretty clearly for quite some time.
TV/Radio rights is also a weird thing contractually so I'd imagine that factors in somewhere. Good. More for us. f*** everyone else.
Regarding contract, compared to Doc's pay from the Devils when he started doing national games, I'm sure Sam has been getting paid enough money to make national games not worth his time for a while now.