Mixer losing instrument names

I think that’s what’s going on. Very large score using MIDI endpoints and VEP7

Many of the unpitched percussions are missing, but I have these odd blanks, which I’m guessing are them. Unsure as there are lots of them and I can’t tell what Dorico is up to here.

If you end up with channels in your plug-ins that aren’t routed to instruments in the Endpoint Setup dialog, then they’ll be blank in the Mixer because they don’t have anything routed to them.