It sounds as though it's booting the rescue dash, which means it can't find the hacked dash on E.
If it's modded with Kingroach the dash should be at E:\Dash\default.xbe, if modded with Krayzie it should be at E:\Dashboard\default.xbe. From your description of the rescue dash it sounds like Krayzie, but you should know as you modded it!
Your relative needs to boot with a rescue disc (CASH would be sensible) and check the E:\ partition for those files, and replace them if they're missing. CASH has an option to reinstall a Krayzie softmod - but you lose the contents of your E partition, including any gamesaves.
FYI, Slayers and AID are no use in helping to fix softmods, apart from giving you FTP access......