Extract/Run the Dell bios EXE, get the file PS-A13.bin and mod it, guide here: https://winraid.level1techs.com/t/howto-get-full-nvme-support-for-all-systems-with-an-ami-uefi-bios
Use AMI MMtool method and insert small DXE NVMe variant.
Compare original and mod files with UEFItool, for pad displacement.
Read also: https://winraid.level1techs.com/t/guide-how-to-flash-a-modded-ami-uefi-bios