My assumption based on the following observations:
- The wish to integrate Deezer into roon is first mentioned in May 2015 (nearly 5 years ago) and many roon lab users are supporting it (see the many different threads to Deezer in this forum).
- Nevertheless Roon Labs management never pushed this topic (see Deezer support @danny “oh wow… Deezer… totally forgot about them!”
- Even since Roon Labs management knows (October 2019), that Deezer would be open to discuss it, nothing happens (see https://en.deezercommunity.com/got-an-idea-50/roon-compatibility-843/index4.html#post147454).
- In my theory it should be a big win for Roon to integrate Deezer a much more popular music streaming provider than Tidal or Qobuz.
- So the only reason in my eyes, why Roon Labs management is waiting that Deezer will contact them is they expect money or ressources. But this never will happen in my eyes, because Deezer has the content, Roon has only a software.
Unfortunately the result is, we will see no integration of Deezer in near future 
Hopefully I am wrong.