TiVos use a separate Original Air Date field in the guide data, not the one in the Description or the R flag. Press Info and scroll down to see if it's there. If the OAD field is present, it's within the last 28 days, and your TiVo hasn't already recorded that episode within the same 28 day period, it defines it as First Run.
In your case it looks like SPIKEHD is sending reasonably accurate descriptions to Tribune Media but they're probably leaving off the OAD altogether. That's actually the worst case scenario because if the old episodes all had the same generic description you could replace the Season Pass with an auto-record Wishlist that excludes that description. This is called the Tupper method after the member who thought it up.
You might be able to set up an ARWL with multiple exclusions based on the Description. Something like if "(2009)" or "(2010)" or "(2011)" etc is in the description, don't record it.