Actually, on second thought, I haven't opened Galaxy Forge for a long time, so check to see if there's a "Ingamename" (or similar) setting when you create a player. That might be able to override the random name choosing, I believe that's how it works for planets already.
As far as the English.str file for AI names, what I'd suggest is opening one of the player entity files, finding the list that references AI names in the .str and then find them to see how they're labeled. Then you can just add your own string definitions modeled after the way they're already set up, and increase the string count at the top of the file. Then just replace the string names in the player entity file.
For example, I don't remember how everything is titled, but say playertech.entity has this line: AIPlayerName0 "IDSTechAIPlayer0"
You open up English.str and it should have something like this:
StringInfo
name "IDSTechAIPlayer0"
value "Nithleim Rebels"
All you have to do is add your own:
StringInfo
name "IDSFederationAI0"
value "Starfleet"
and increase the number of strings count by 1 at the top of the file. Then go back to the playertech.entity and change AIPlayerName0 "IDSTechAIPlayer0" to AIPlayerName0 "IDSFederationAI0", or whatever.
Note that I made up the names as examples because I'm at work and don't have access to the actual stuff.. but it should be something similar.