You're on a dedicated server?
If so, I'd think that would lessen the chance of DH screwing something up, since they wouldn't be poking around on it. Example: Shared customer asks for something deleted and they delete something of yours by accident... that would be bad, but unlikely.
Also, do dedicated customers have .snapshot directories? I have no idea, but if you can't access them, it could be a possibility.
In any case, if you have a lot of big/important files, you might want to go with an online backup service (in addition to your own & DH's backups). That way, if something like this happens, you can do a much faster transfer during the backup process.
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