A few of the recent auctions on which I've bid, many of them from the same seller, have all ended up being exactly at my highest bid. Those placed without AS, that is. For the few that have been placed with AS, I generally get them several dollars below my snipe bid.

I suspect that the seller is seeing what the high bids are, and having others place bids to run up the cost of the auction to the highest bid.

How to prove this?

Contact ebay.

How will "contacting eBay" prove shill bidding?

Your reply is not an answer.

Correct. It’s a suggestion.