The raid was triggered by entering the second village, since it didnt trigger as usual in the jail village shown in the screenshot, most likely due to not having any villagers.
It would be impossible for a pillager to enter the room shown in the screenshot, as it is protected by iron doors. However, there would be nothing to protect the villagers if a randomly spawning group of pillagers happened to appear in the room, although I have never seen them spawn underground before.
Henry Towberman
The raid was triggered by entering the second village, since it didnt trigger as usual in the jail village shown in the screenshot, most likely due to not having any villagers.
It would be impossible for a pillager to enter the room shown in the screenshot, as it is protected by iron doors. However, there would be nothing to protect the villagers if a randomly spawning group of pillagers happened to appear in the room, although I have never seen them spawn underground before.