In an effort to not embarrass myself any more than is absolutely necessary, I won't disclose how long it too me to figure out a) what the problem was and (more importantly) b) how to fix it.
The short fix, which I'm writing her so I'll (hopefully) remember is:
Removing ACLs
The setfacl -x
It is also possible to remove all ACLs for a file or directory with:
setfacl --remove-all
To remove all default ACLs for a directory:
setfacl --remove-default
setfacl --remove-all
To remove all default ACLs for a directory:
setfacl --remove-default