Re: sd strat hotrails bridge salvageable?
Boy . . . thats pretty bizarre. I thought you meant one wire came unsoldered from the base, but thats the whole 5-conductor cable thats been sheared off. Something had to do that. That cable wouldn't have just fallen off.
Anyway, if it was me, I'd remove whats left of those four wires, and ground, and completely reattach the new cable. Be sure to make a nice diagram first, showing where each color goes.
And again, you want your soldering skills to be up to snuff before attempting this. If you aren't sure, perhaps send it back to SD. (Or, get a tech.)
Do you still have the original cable?