I can't suggest anything to work around it with TiVo other than making a bunch of manual reccuring recording entries. Or a WishList. Unfortunately, I'm not up on current TiVo versions to give much more specific help (older TiVo software didn't have wishlist capabilities that were extremely flexible.) If you can restrict a wishlist to a particular channel that would be a good start.
But I can tell you why what you're trying to do isn't working. I'm pretty positive the TiVo creates its season pass using the EPG data's ShowID. You would think that regardless of the teams playing, and therefore the possibility of alternating titles, the ShowID would remain constant if it's a regular program slot.
For instance, CBC's "Hockey Night in Canada" likely has a unique ShowID, regardless of the teams playing.
I'm running SageTV now as my full-time TV. I think even with that program I'd be stuck unless I used a specific repeating timeslot (and then it would be either once per week or every day - not ideal).
Bruno