Thanks for the report!

Thank you for finding this, will be fixed in next build. Shard now appears in front of wall, and talking to the shard will now destroy the wall if it is not already gone. Thus, if you leave postfight and preshard, when you come back you can talk to the shard to proceed. If you come back postshard, wall will be gone by default.

I also believe the shard’s previous location was preventing the Husk from spawning due to the two overlapping, this is likely why leaving and coming back may have been failing to respawn the boss. This issue is being investigated. Again, thank you!