Almost no pulse, sunken eyes, non-responsive, that's normal for these guys in freezer mode:P. IIRC, it takes a few weeks after emerging from brumation for the cryoprotectants to flush, so they have some capability of withstanding thaw/freeze cycles in the spring.

I'm not saying it was wrong to take it in or anything and hats off for caring. I probably would have just moved it out of the way and covered it with some mulch so it wasn't so exposed or in risk of being stepped on accidentally, that these frogs can withstand freezing is just one of their astonishing traits.