Hello,
There seems to be something we're missing...
Is there something stopping you from deleting the history directly, by deleting the Auction entry (in HikaAuction => Auctions)?
Another solution if your store has not had a production phase (and therefore a real order), is to copy (clone) your relative product (with a new Id), which will then be without any bidding history, and to unpublished your product, and replace it with his new clone.
But I insist don't do that if you have any real order history (with this current product), because this may disrupt the administration and compatibility of orders placed.
Regards