Pillagers not appearing after or during a wave of a raid.

A Raid started in a village that lost it's original villagers (I cured new ones), and after defeating one wave of Raids, the next wave started. This wave, however, did not spawn any mobs. I think one of my 2 villagers went missing though.

 

Let me note that there is a cobbblestone waqll surrounding the village that helped it survive the first Raid.