Hello,
the first problem is that after restricting the component in JoomSEF setting, you still see the SEF URL. This is because JoomSEF already remembers the URL, so you need to delete the records. You can do this by switching the JoomSEF off/on, pruning the records or deleting them manually.
If it works after this, than the problem is really related to the SEF translations for this component. We will then consider writing a supportive extenstion for it.
Regards,
Honza