Dont repot, just increase watering. Phals should only just dry out between watering, and i always use the top layer of medium as a guideline-if it is dry ontop, flush with more water. You should see new roots starting to emerge in a few weeks/months, and you could also try using some liquid root hormone (maybe 2 drops in a litre of water?) and flush it through. I would cut the dry roots just before where they meet the plant, and carefully pull them out.
And icecubes? Ive heard of these so called ice phals, but its all a myth. Just sit the plants on the bench and flush with water for about 15 minutes at a time, and repeat, again, when the medium looks dry.