Is it safe to remove this “RST” entry from the EFI System Partition?

Formating Efi system partition as FAT32

During an install you can remove all the critical partitions, of which the EFI System partition is one. You do not have to pre-format a drive during an install. Just remove the Critical partitions ( MSR, EFI, Recovery and OS)and leave unallocated space.
The install will take care of the rest.

You can delete the partition and use the Diskpart create partition EFI command with qualifiers, if necessary. If you have already created the partition, try using Diskpart from a command prompt (Shift+F10 during the install) and format.

If you need to convert a drive from MBR to GPT or vice versa, you need to remove ALL partitions.