0/3 on agents being able to make this work. This one told me she couldn't do it and that it wouldn't be available in March 2024 yet anyway, while reminding me she couldn't waitlist it. She also wouldn't bother asking the support team when I asked.
I've triple-checked on the date I have it booked and there's award space in First on both AA and BA. Guess I'll continue to try again and ask them to escalate it if they can't do it.