Tobi isn't Obito.
Okay so bear with me it may get a bit confusing.
Every user of the sharingan has 2 dojutsu -> Izangi, Izanami
Every Sharingan user with a3 tomoe sharingan can use these techniques at the cost of an eye.
Every user of MS has two traits that are different from on MS user to another.
Take for instances Sasuke, His right eye controls his Tsukiyomi where his left eye controls Amarasu. The combination of the two MS creates Susanoo.
That being said Kamui is a single MS attack as far as we know.
Kakashi has Obito's left eye.
So for Obito's set of eyes his left should have been Kamui and his right should have been another illusion dojutsu like Kotoamatsukami or Tsukiyomi.
Sooooooo I can say with some certainty that Tobi is not (T)Obito