They signed him to a mL deal over the winter and he played in Spring Training (27 PA, .881 OPS). It feels like 20 years ago to me, too.
He was available cheap because he is recovering from a neck surgery for an injury that sapped his offense for the last few years. If he is actually healthy, a Vazquez-Plawecki-Lucroy tandem could be good on both sides of the ball. That he isn't included on this roster suggests that he may not be healthy.
edit: McWilliams follows up! "[Lucroy] not being on roster is due to his contract being reworked."
edit 2: Alex Speier clarifies that a bunch of teams are reworking deals that had minor league deals with opt-outs if players were not on the 25-man roster by a certain date. Their contracts need to be made compatible with this season's roster rules.