A few notes I can share... scenes 218-220 were indeed shot- they're included in a daily shooting report I have. I have one photo of Quentin close-up with the candelabra, and you can tell from the background that they are at the bottom of the staircase, about to separate.
It was cut out of even Dan Curtis's director's cut, though, most likely just to tighten things up a bit. The dialogue from this scene between Alex and Quentin was edited down and plays over the shot of Carlotta in the tower in the director's cut, and yes it exists. It was replaced with the solo Selby "find Carlotta" voice over to help make sense of the chopped up ending in the short version.
One thing to keep in mind in many of the scenes, is that the dialogue in many of the scenes was all adjusted, tweaked, revised slightly on-set, which makes things play a little more naturally, but has been sheer hell from a dialogue re-looping standpoint because there's no document that exists which accounts for all the on-set changes. Lots of trial and error and frustrations in the booth, I can tell you! The basement/skeleton scene loss is a huge disappointment to me, and I believe that dialogue would have been significantly revised in filming, probably dropping the Laura laughing line and having some minimal lines of explanation to clarify that the skeleton is Charles, and he's lying atop Angelique's coffin, with her inside it.
The shot of the skeleton hanging from the tree was just on-set goofing around. I have the contact sheets from this shoot, and it's not supposed to be Angelique- it's Charles's skeleton and is dressed in his rotted shirt- that's why there's that shot of Selby standing next to it, as it's his character. They were shooting publicity shots of Selby, and the crew just ties a rope to the skeleton and pulls it up off the ground to get the shots with Selby, then afterwards a few shots of it by itself in the tree. I was thrilled to find that contact sheet, as it always appeared to be some shot of Angelique's body rotted to nothing and hanging there, and intriguing, but impossible scene to match to any of the scripts.
In the final filmed version of the Gerard fall to his death, Alex says, "Looks like the old Bangor local is gonna be running late tonight." Thankfully we have that audio as well. His face is off-screen for the tail part, and if we didn't have the original recording, we would have looped it as "B&M" which would have been unfortunate.