Our vet called back and said since it is cold here, her hooves may feel hot, or some horses just have hot hooves because some horses just have more blood flow
Of course with little information, who knows what state your ponies are in & perhaps I've misunderstood, but your vet gave you that over the phone 'diagnosis'??? Assuming she hasn't seen the horses very recently, examined their diet & weight(the one in your avatar looks rotund), examined their hooves, etc, I would be thinking she either knows very little about laminitis & hooves, or she doesn't care much. If so, I'd be looking for another vet!
I would be inclined to treat the horses as acute laminitis cases, until it has been properly ruled out. People often think of hay as 'poorer' than grass in relation to laminitics. It does lose nutrients in cutting/drying, but unfortunately grass only loses sugars when it's growing, so hay is just as high in sugar as the grass was - & most hay these days comes from 'improved' cattle fattening rye grass or such. I'd be soaking & draining the hay before feeding to the horses(& donks) to leach out some of the sugar.
If their feet have been allowed to overgrow, this can exacerbate any systemic problems. We all live in 'the real world', but it's best to keep feet trimmed frequently enough to keep them in good shape, which is especially important if you suspect they are already compromised in some way.
More info on management, exercise, etc & hoof pics(see link in signature below) would be helpful if you would like more specific opinions.