Since you say the same Ventoy USB drive works on a different Dell, it sounds like a problem with the 3558? Did you try a 'reset to defaults'. Try any other boot manager/loader like Easy2Boot? If both Legacy and UEFI booting to Ventoy show the same issue, maybe it has a RAM or ...
(unset) * checksum= If set to "y" or just "checksum" without arguments, performs a self-test of all files inside ${install_dir}, and continue booting if ok. Default: (unset) * cow_label= Set the filesystem label where COW (dm-snapshot) files must be stored. Default: (unset) *...