+1 award redemptions are often tricky. If there is no *a availability for the sectors he wants, there is no point switching to US airways or another *a airlines like EVA. If another airline or ff program has better availability on those sectors, then that would be a reasonable alternative. 50k miles on UA = *gold on EVA anyways, so I am not sure earning *G directly on EVA has any additional benefits, since UA has a pretty decent redemption program. Also with US airways merging with AA, there will not be much benefit of it's status for his EVA flights.

I am sure he should be able to redeem his miles eventually. Just that not getting a couple of wishful redemptions should not be a deal breaker.