My one and only trip in one of those things and it was nigh on impossible to keep it in a spin after about 1 1/2 turns but that doesn't mean things can't go wrong - if you are doing no more than 1 1/2 turns 3000ft is not an unrealistic entry height.
I would guess the recovery at 700ft was more likely because that's how long it took them to recover, rather than a deliberate attempt to put in 4 or 5 turns from 3000ft
however I would doubt that it was 700ft.... you'd be properly cacking your pants, I don't know what the rate of decent is in a 150, but imagine a good 5000-6000 ft per minute minimum....