If they werent taking F/T rats, ideally the backstep would have been to live rats, but its not the worst thing in the world. Just maybe a little more work. I wouldnt worry so much about mutiple mice per feeding. Its generally considered best to have one larger prey item vs a few smaller prey items. In my experience, after that first prey item is swallowed their mindset changes over to defensive mode and they just want to hide. A lot of snakes ive tried to feed mutiple prey items just werent in the zone anymore by the time I offered the second. I would recommend making the switch to live rats your priority, then worrying about the number and size of prey items after that. Then of course F/T if you still want to persue it. Best of luck = )