Slug in use, but wrong series

Sonarr version (exact version): 3.0.6.1342
Mono version (if Sonarr is not running on Windows): 5.20.1.34
OS: Docker on Ubuntu 20.04 ARM64 using linuxserver.io/sonarr
Debug logs: Relevant lines below
Description of issue: Two series have the same name but different years; cannot add as slugs identical

I’m trying to add “The Invisible Man” from 2000 (https://thetvdb.com/series/the-invisible-man, ID 74460) but I already have a series called “The Invisible Man” from 1975 (https://thetvdb.com/series/the-invisible-man-1975, ID 76793). When I try to add the 2000 series, I am told that the slug “the-invisible-man” is already in use by the series “The Invisible Man”.

Invalid request Validation failed: 
 -- TitleSlug: Title slug 'the-invisible-man' is in use by series 'The Invisible Man'

The series have the same name on TheTVDB.com, instead of the usual practise of adding the series year to the title if there is a title clash. The 2000 series has been “certified” by TVDB and so I cannot edit it (https://thetvdb.com/series/74460/translate/eng). I can edit the 1975 series but that would break their editorial rules as it’s the first TV series with that name.

Can I force it to use a slug of “the-invisible-man-2000” somehow?

As this title is “certified”, it might be their policy now to not have years in the title. Would it be worthwhile updating the slug code to always add the year if not already present?