Telling my (nb25) bf(m28)’s best friend that he needs help - crossing a boundary?

My partner is in the midst of a deep crisis right now and I’ve tried to do what I can to help and support him but he’s shut down entirely and won’t talk to me or listen to what I’m trying to say - understandable.

I’m incredibly worried about him, and he feels worthless. Would it be a breach of trust/wrong to message his best friend that he misses a lot and go “hey, i think [BF] could use a friend right now - please don’t tell him i said that, but i bet he’d appreciate someone reaching out.”
because i know he’s not the type to reach out or communicate what he needs. but i don’t know if that’s meddling.