Linked video shows vertex tools failing to allow editing of curviloft created surface-mesh. If created with sandbox tools it will edit. sample model file attached.
The most obvious difference in your vid is the face colour. Vertex tools has the option to ignore back faces, so it looks like you have that option on.
Reverse the curviloft face and try again.
That’s it!!! Thanks. despite the many admonishments to pay attention to face direction, still not something that is top of mind. Will be now!