Helped a Skyteam coworker book this. Here's some lessons learned.
DTW - AMS is the only A350 route to Europe for the summer valid fare window. If you're looking for the holidays, ATL-AMS should be available and possibly ATL-CDG. For those struggling with finding A350 availability, specifying DTW and AMS in the routing will give you the right connections, though there is also an A330 flight.
KLM flying LAS-AMS 3x weekly on a 787. There is also SLC-AMS on a 787. LAS-SLC-AMS-BRU is a valid routing for a few more miles to get more 787 time.
Amex through IAP couldn't ticket the A350 routing we fed them, instead settling for 787's in both directions. Inclusive of booking fee (no OJ's) we ended up at ~1440. I was unaware of this program prior to this thread. Thank you all for the education.