AFAIK, the only developer that Leica ever "recommended" was Ethol TEC. This developer was used when Leica demonstrated their lenses in North America. They didn't really recommend any particular brand of developer and usually kept the bottle out of sight. Why would they recommend Rodinal and antagonize all the other developer manufacturers. Companies just don't do this.
Leitz aren't a US company but their official publications did make recommedations about developers particularly in Europe, at one time there was far less cross availability of chemistry between the US and Europe.
Of course US publications like the Leica Manual (Morgan) recommended US developers but it wasn't an official Leica publication. Recommendations changed as films were improved.
Leica themselves published their Two bath developer and Rodinal and Neofyn were also both recommended in their newsletters.
Europe differed from the US in that all the major manufacturers made a Rodinal type developer, Ilford - Certinal, May & Baker (now Chanpion) - Azol, and Kodak -Kodinol.
In addition to compete with developers like Neofyn (later changed to Neofin) a Beutler type developer, Ilford released Hyfin, Kodal - HDD and Johnsons - Definol.
So there was a different approach to developers for miniature film formats in Europe compared to the US and this began in the early 1930's and lasted into the 1970's with Rodinal and Neofin still available today.
Ian