Mildly surprised they couldn't find a taker for Yabu to open up a TPE by including a second-round pick with him, but the Cs may have felt even a second-round pick is too much to give up for a $3m trade exception, which is probably right in retrospect given their new potential "salary ballast" they've acquired this year (Kanter, Theis, and you can also get there by packaging together a couple of the other non-starters like TL and Wanamaker or whatever).
Edit: I don't think this has anything to do with Tacko, btw. Much more likely they have someone else in mind who they can bring in for the vet min, or they don't have anyone specific in mind but want to have that open roster spot as the offseason continues.