Board Thread:Episode Discussion/@comment-26512661-20200118161649/@comment-4010415-20200127002315

Ironwood could have dragged Watts back to be put in jail, but I wouldn't be surprised if he dropped Watts into the lava to perish.

Also, I think the Sherlock of Watts' story is Ironwood. Ironwood never really acknowledged Watts' genius to his satisfaction, but Salem did, so Watts sided with Salem instead of staying by Ironwood's side.