I’ve found similar issues. OSL-CDG-NBO-XXX. OSL-CDG available CDG-NBO-XXX available but as one ticket doesn’t work out. Agree that shouldnt be a married segment issue and when I start thinking the booking engine can’t handle it, then of course it offers me 5 point connection (in economy). So I would just call. Now I don’t know what you’ll get as an answer but imagine if you just build it in the sequence it does work, it shouldn’t be an issue.