Keynote Collaboration Fonts Missing

Hi

We use a font in for our brand which often is reported missing when using Collaboration. The font is called Söhne and when keynote reports it as missing it calls it Sohne. While collaborating you can't replace fonts with the Replace Fonts tool- it's greyed out.

Our workaround at the moment is to complete the presentation and the download it to replace the fonts before final presentation. But ideally this issue would be addressed.

I suspect this is a similar but different issue to this:

https://origin-discussions2-us-dr-prz.apple.com/en/thread/252633559

All collaborators have the same versions of the font installed, if we share the file on a file server or airdropping it there's no issue (but we don't have the collaboration functions obviously.