I've fixed this in wimlib-1.13.0-BETA3. The file \Users\test\AppData\Local\Microsoft\Outlook\some.pst will now be included in that case.My resulting WIM is including the someother.pst (expected because it wasn't excluded) but it does not include \Users\test\AppData\Local\Microsoft\Outlook\some.pst because the parent directory \users\test\AppData is excluded. \Users\test\AppData\Local\Microsoft\Outlook\some.pst exists and is confirmed present when I capture the wim.
Similarly, in the original case reported by bliblubli, the directory \Users\test\AppData\Local\test will now be included.