The file name you are looking for is InvadingFleet.lua .This is found in the Story folder, a subfolder in the Scripts folder.
Assuming you cannot find this file on your computer, below is how I found the file on my computer. Depending on if you have your files stored locally or on steam, I showed two different paths where the file might be stored.
Locally:
C:/Programs Files(x86) / Steam / steamapps / common / Star Wars Empire at War / corruption / Mods / (Whatever you named ICW) / Data / Scripts / Story / InvadingFleet.LUA
Steam:
C:/Programs Files(x86) / Steam / steamapps / workshop / *32470 / *1125571106 / Data / Scripts / Story / InvadingFleet.lua
* I'm not familiar with how Steam workshop files are named (probably some hex code but I'm really speaking on things I don't know), but these were what the files were named when I subscribed to them on Steam. Leave out the asterisks when if you input the pathway manually.
Hopefully this helps!