My experience:
All calls were made between 12:30 PM and 1:15 PM CDT. All calls were made to 1.800.297.3276.
First call: for my wife's accounts. She got a PRG this year, and a Business Gold from when I don't remember. The rep put me on hold, did his research and came back confirming the eligibility. He said he made notes on the MR account. I asked if it's necessary to call back to get the points to post. He said most likely yes. He asked if I wanted to add the AU's right away, I said I'd rather do it online to save all the back and forth about spellings and etc. He confirmed it won't affect the promotion eligibility. I guess not, given how manual this thing is set up. So my plan is to do it online later. In the end, I asked if the Business Gold qualifies. He looked a little bit and said yes. He said it's one MR account anyway, and he added notes to mention it as such. I am not quite sure about it but let it go, thanked him and hung up.
Second call: for my own accounts. I've two long standing accts, one personal Platinum and one business gold. The lady taking the call right away said they got a lot of inquiries about it already, it's not in AMEX' system whatsoever anywhere and quizzed me how I learned about it. I said never mind and hung up.
Third call: for my own accounts still. The guy put me thru a long hold, and in the end said the promotion is targeted and my two accounts are not.
Don't know who to believe. I'm calling it a day, a qualified half-win. I'll add the 5 AU's to my wife's two accounts later today, and wait till end of Sept to check back.
Thanks for the thread.