EA FC 26 PC "error on our end" after AntiCheat

Game fails to launch after AntiCheat: returns to EA App or gives "an error on our end has occurred, please try again later."
System: Ryzen 5 5600X, RTX 2080 Ti (latest WHQL driver), Secure Boot/TPM2.0/UEFI enabled, Windows 11 24H2 and 23H2 (both clean installs).

Troubleshooting done (all repeated on both builds):

Clean installs of Windows, drivers (DDU), EA App, FC 26, EA AntiCheat

All overlays off, .exe files added to Defender/AV exclusions

Ran as admin, cleared EA App cache, C++ redistributables repaired

SFC/DISM, network reset, new admin user, new install location, clean boot

Everything from EA support and forum/YouTube guides

Result is always the same—game will not launch past AntiCheat, nothing in logs, not account-banned. Seeking dev or backend fix. DxDiag available.