Yup, though they have confirmed on Instagram that the Crusader 5.56 upper will not fit the MCR or WK lower.
Yeah, sadly...
There could be a purpose to Crusader firearms being a separate lineage. By starting as a 9 mm PCC platform that happened to get a 5.56 upper available for it, while making both incompatible with WK and MCR, any named specific action to mark the WK and/or MCR as prohibited in an OIC or FRT change would not affect the Crusader, since it is a new, unrelated firearm.