It's possible that you're bidding a little too early for Baltimore Inner Harbor. July 31st is still over two months away and sometimes hotels don't release their rooms to Priceline this early. I wouldn't bid too high or compromise on star level or zone this far in advance. That being said, if you Click on "Baltimore North," you'll find the Hunt Valley/Timonium Zone, which is right along the Light Rail line which can take you to and from the game.