The Bitter Cold quest line not progressing after resuming

[Mad Queen Malafide.7512]

I was playing through The Bitter Cold (Living Story season 3). After brewing the thax elixer, I went up to the cave to face the Abomination, but didn't complete the entire mission (I don't remember if I actually beat the Abomination). Just around that time the new living story for season 4 was released, so I abandoned this quest line to check out the new content. This week I tried to resume my progress on The Bitter Cold. I made my way up to the cave with a new thax elixer, only to find that there was no abomination. It would not progress. I also cannot go to Sorrow's Eclipse and speak with Deep Water. Currently the quest says I must track the abomination, but he isn't there. It refuses to progress. Redoing the entire chapter might allow me to continue, but I figured I'd mention it first, so it can be fixed.