I received mine today. Tested both discs on my LG 4K Blu-ray Player (UBK90) and PS5 (Slim) and kept getting the region error code for everything. It seems these discs are both locked to Region B.
The only solution that worked for me was changing the PS5 to Region B. This is a feature they added to the slim 2023 model. Keep in mind they only allow a limited amount of switches. This does not interfere with your games from playing. Since I have the other player I plan on keeping the PS5 Slim as a dedicated Region B option for any others that may have this issue in the future.