We may find out if there's a previously unknown active route marker task when the episode airs tonight, or in one or more of the insider videos CBS will post later tonight, or from the Racers themselves, either in elimination interviews or later after the season airs. We've even learned of some tasks at TARcon!
(The exit interviews were how we learned about that first roadblock ever that wasn't aired (cooking an ostrich egg at Songwe Village) and it was included as an extra in the TAR 1 dvd set.)