Interesting !
I`m a born and raised Floridian for my currently 69 yrs. and never omitted the "U" when pronouncing Ambulance, or inserted a "R" when pronouncing washing, or washer, though have heard that used by a occasional Georgian small town hick from the back woods up there, that I encountered !
My born, raised in, and GA. Tech educated father, would not allowed me to, at least in his presence, as he was a stickler for doing all things correctly.