The issue described in Windows erased Systemd-boot entries in UEFI appears also on a MSI Laptop. Following the steps to resolve it, the Linux Boot Manager entry is successfully restored but no entry for EndeavourOS is available to select in the menu when booting.
The missing entry corresponds to efibootmgr not showing it. In the past under grub, --force did the trick:
That same problem repeats whenever Windows decides it. I believe, it is related to shims even if Secure Boot = Off. Some other Linux’s do not experience the problem.