I apologize in advance if I don't provide proper detail; I am new to server stuff and am looking for general advice about this issue:

I was helping out a client doing web design last month. They have about a dozen static sites on one server. The sites are all built on Joomla, except one which I built on Wordpress. Everything was working fine last month when we did the redesign but all of a sudden this morning, every single file on their server got deleted: every web page, file, and all e-mail addresses.

I phoned the hosting company (alliancewww.com) to ask, "why did every single file suddenly delete off the server?"

They said, "because someone must have deleted it." I said, "well no one did." (Which I'm pretty damn sure no one did.) They said, "you can pay us to look into the problem." I authorized $150 for them to look into the problem.

About an hour later, everything was magically re-instated. The host said they had a back-up of everything and just restored everything.

What I'm wondering:

Does anyone have recommendations of logs I can go through to investigate how the files got deleted in the first place? I've checked out their cPanel logs but found nothing.

Is it likely that this is a mess-up on the host's part?