Actually, your second 2P gift was perfectly legit, and should have gone through on your old account. Some phone agents will claim that you can only nominate someone without status, but this was not true for any Elite Choice promo except this year's (and AFAIK nobody has yet been nominated under this year's promo).

I was re-nominated to 3P while still a 3P, and nominated to 2P while a 3P. Your re-nomination should have been allowed. (FWIW, doing it online should have worked just fine... that's how I got nominated every time.)

That said, now that you have two accounts, I have no idea about what to do... though I would think UA would let you combine them if you can claim to have opened the second one "accidentally" (e.g. you forgot about your first one). Since you still have a trip booked on your old one, the "accidental" explanation probably won't fly, but I don't really see why they wouldn't combine the two accounts as long as you didn't get sign-up bonuses or other benefits from having two open at once.