Yann Golanski wrote:
The first one was from Tomiki himself who said that Ueshiba never asked him to leave the Aikikai nor asked him to stop teaching randori. Shodokan home page reference
What I remember is an interview with an Aikikai shihan (don't remember who) where he told how osensei would be irritated when people mentioned Tomiki's name, and complain about how he introduced competition in aikido. It could be an "urban myth", I do not know.