It is unclear whether the Navigator module will include hidden tabs or not and since your tabs aren't in the main menu structure, that is something you really need to consider.  TheDNN.Menu lets you custom build a menu but it is unclear whether it can dynamically populate or not (but luckily they have a demo so you can download that and see).

To throw a third module into the mix, you could consider SW.Menu -- it allows dynamic population of menus (you can set a parent page as its start point or let it start at root) and the option to include hidden tabs as part of that dynamic population.  Additionally, you can build a completely different menu structure on your own if you want.  It supports trees as well as horizontal and vertical menus.  Best of all, it has a trial you can download and test it out to make sure if it would really fit your needs or not before you commit to purchasing it.  There is nothing worse than purchasing a module and finding out it doesn't do what you want it to do.

Good luck!

The problems I was having with the licensing were due to localization, and thanks to the good work of Jon Seeley from SeeleyWare, this has been corrected.

Now i SW.Menu supported localization of the tabs, it would totally suit our needs.