I am building an underground trading hall where villagers have 3 block long rooms that include a bed and their profession block. I've brought an unemployed villager to their room, 3 blocks away from an unclaimed profession block, yet they do not claim it. There are no nearby villages/villagers around the area.

Is it possible that somehow, dead villagers from the current or previous versions are claiming the beds and worksite blocks? (I had villagers around the general area ever since MCPE 1.9, where a few have died here and there)

I created a test copy of the world and killed all the villagers except the one in the picture and the blocks are still being claimed by a villager somehow. There are no nearby villages with villagers to claim it.