Joining Parallels Walls With Element.JoinGeometry

I am a long-time reader and a first time poster.
I am having some issues using the Element.JoinGeometry node successfully to join finish walls to the main, structural wall. I created a script that models finish walls based on selected rooms in the Revit model. I have successfully detected which finish walls intersect the main walls using the Geometry.Doesintersect and matched the intersecting walls in pairs to feed into the Element.JoinGeometry node.

The node returns an error that the Elements are not intersecting although it does successfully process three of the wall pairs. I have confirmed that all the pairs are correctly matched and do in fact intersect. I cannot figure out why some wall pairs are working and others are not. Any insights on why I may be experiencing this issue?

I wanted to update anyone that was interested. I was able to get it to work with the list structure I already had by simply using the Clockwork Node Element.Join.Geometry instead of the OOTB Dynamo Node. It works perfectly now.