Hey RedSorc, thank you so much for the video explaining your strategy on the final boss. While messing around with the final boss I found two more safe spots you can use to wedge the remaining dps into so they don't get blown back. It's right where the green fence ends behind the bonfire on either side of the stairs. If you align it properly the cross ignition should go right between your dps.

Here is a video where you can kinda see it in action.
https://www.twitch.tv/videos/335749547