Tor Browser bookmarks should be located in your Profile Directory ~/.local/share/torbrowser/tbb/x86_64/tor-browser_en-US/Browser/TorBrowser/Data/Browser/profile.default or somewhere very similar.
You can open about:support in Tor-browser to check and see what your Profile Directory is.
I have not tested your use-case but if the bookmarks are not preserved you should be able to import them from your backup.