Solid issue: Model no longer displaying volume

I have a model of a game space ship design I am playing with. Sketchup Web is apparently no longer considering it a solid model after I used the Follow Me tool to add some detail. Sketchup will no longer show a volume in the Entity Info. I have went through the model removing all extraneous internal geometry and fixing incorrectly facing faces that I could find that was added when I used the Follow Me tool.

Interestingly I downloaded a copy of the file as a .skp to look at in my older Sketchup 2017 Maker program and used the Solid Inspector 2 plugin. That tool says the model is solid. Is there something I am missing here or have I run into some type of limitation of the free Web version of Sketchup?
Can anyone suggest anything I may be missing on why this model is not considered solid?

If you attach the model we can check it.

You compare two differend approaches to see if your object is still a solid.
Solid Inspector 2 is to there to find errors (and ultimately tells you it can’t find any more issues to then conclude that you are dealing with a solid object).
The SketchUp Free web version like any SketchUp version just tells you if the object is a SketchUp Solid (plus its volume) or not. Without limitations in any version. (FAIK)

Share the model so we can look at it.

Yes, the issue could be resolved very quickly if you would upload the model.
Solid inspector isn’t infallible, there are some very simple ‘errors’ that it can’t see. The experienced human eye is often better than an algorithm.

Here’s a very simple example of a shape that fools Solid Inspector but is not technically a solid.


And the reason is that the edge in the middle is attached to four faces instead of the allowed two.