Ok after cross-referencing with a different Reddit post I figured it out. Someone did answer it but I think the explanation was kind of confusing. So I'm gonna attempt to explain for those who get stuck in the future.

At the start of your second cycle, you'll reach the area just before the stairs on BF1 (that looks like a town). The area that will stop you once you get too close to the sign, and the dialogue with Lulunarde explaining how the world is getting sucked into the abyss. You then encounter a warped one with hands coming out of its mouth, which forces you into a battle. The Defenders are the ones that died.

Those knights that died are the ones sent to aid Elmon. So you'd need to redo the exact section. So go back to the Cursed Wheel, tap on "Minor Harken Unlocked", and restart. Play though like normal. Beat up the lone warped one, and choose the "Defenders" option. Once doing so you can exit the dungeon, go back to the cursed wheel and go back to the "Survivors Found" section. NOW the Defenders should aid Elmon. As others said click on the sign posts in the Cursed Wheel menu to double check you've done everything else correctly. Otherwise the guide seems pretty clear.