Thanks for the update! I ended up buying some physical Delta gift cards at a local grocery store that was running 4x loyalty points on gift cards, and used my Gold Amex to get 4x at grocery stores. Then applied those gift cards to a flight and made sure the extra out of pocket was charged to my Plat Amex and was ~$220. Hopefully that will trigger the airline credit.

Had a really convoluted time getting everything applied since I also had an eTicket from when I made use of the 40th Amex Plat offer for $40 off a Delta flight a few weeks back. Had to purchase a ticket with the gift cards that was as close to the value I had ($575) as possible, then change that flight to the flight I actually wanted to take, apply the eTicket credit and then finally pay with the Amex. Boy oh boy to save $40, use the $200 credit, and earn bonus points. It's probably not worth the hassle, but it feels good to use all that when the AF is so high...