I think that is a logical conclusion but I don't think is wholly consistent. At Arsenal what he has really wanted is an input, representation at board level etc. He would be given that at Everton.
There is strong evidence of wealthy Russian owners being in the background in football. The reasons for this may be multiple. It would also be worth noting, that in the circles he mixes people would be aware of who is bankrolling Everton and I imagine that would be what is most important to him and his business.
Or alternatively he could come in as the main man. Frankly I do not see Moshiri stopping him doing so if he really wanted too, even if he was unhappy happy about it (why would you jeopardise such a relationship over something that is quite petty?). I don't see that though, I think Moshiri is a much cleaner face as the main man. I also think every option will have been discussed before Moshiri ventured to Everton, so the idea that they are making it up as they go I can't imagine is true.
My own gut feeling, is that Usmanov will by into a holding company. I think they will use debt being converted as equity as an efficient way to navigate FFP rules and adjust the %'s to how they like. I also think they will look to bring 3rd party funding on board, possibly other wealthy Russians, possibly Chinese investment, possibly some of the consortiums close to Moshiri who helped purchase the Liver Building. They will be minority shareholders but have representation at board level, and again the cycle of debt converted to equity will be used to allow the football club to spend substantially while financing a stadium.