No. It's not just maybe. Here're some facts...
This is the ominous line in dependency walker:
Notice it's an error, not a warning. Moreover, it appears for 1.1.15900.4, but not for 1.1.15800.1 or any other previous version of mpengine.dll (I've tested two more, but that should be enough, in this case). So, MS's attempt to kill XP through MSE lies on the mpengine.dll... That's good news! I count on @heinoganda kindly creating an automated updater, from these findings, as soon as he finds time for it, of course!