Something is very wrong there because even if were a legitimate rental you picked up, there is absolutely no reason why they would be charging your card multiple times for the same amount. Typically, at the start of the rental, they would run the full amount plus a deposit (typically around $200), so if you had picked up the car, you probably would have seen an authorization hit your card for around $358 but the charges would not be finalized (i.e. "posted") until you returned the car.

In terms of the charges you are seeing, if the charges are all pending and not posted, then even though it's annoying, there really isn't anything to worry about since they will fall off eventually. If you're not getting help from Hertz, then call your bank and have them look into it.