FWIW:
I don't know if the current version of if Monolingual and DeLocalizer does this, but when TinkerTool System removes language support, there is a setting/preference to:
Don't remove spell checker and summary dictionaries
Don't remove languages from components integrated into applications (I find this most valuable)
Don't touch Adobe applications
Don't touch selected software bundles (as edited by user)
As a consequence of the above, I have never experienced a problem when TTS removes language support packages.