Not on this model, but I have seen double branding on Primero A787 and A788 and some very late model Defys. Weird but its not impossible that it might be authentic.
Yes, it looks like Movado first (silver -same as minute and tachy markings), with "Zenith" added. Interesting. Perhaps some market that hadn't seen Movados prior to the MZM merger, co-branded so as not to scare off the customers.
I have seen quite a few different pieces with both brands, in passing but have not taken a close look at lettering. I would think that they (Zenith) had planned this as a transition period to show that ultimately Zenith was to be thee brand. Of course things changed later. Also perhaps many models like the Pilot/Diver were issued in both brands so as to gain market share by selling to Movado lovers!