To identify who an address belongs to when the name field is blank, export a gedcom with Addresses selected. You can uncheck the other choices under Data to Export.
Open the gedcom in a word processor file.
Open RootsMagic. Open the Address list at Lists, Address list.
Go to the first address with a blank name and copy the street address or phone number.
Go to the word processor and paste that into the word processor's Find search.
Note the name of the person who has that street address or phone number in their record.
Open that person's Edit person screen in RM and enter their name into the Address.
Repeat for the next address.