Giving him no intel will just push the fight high diff for Kabuto instead of mid diff. If Kabuto doesn't know about him then he simply gains intel during battle.
With that said. Kabuto has already keep spacing from Obito's blitz already[
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].
He will start off with snakes around him to track down his movements[
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]. This ability and those snakes striking speed had force Itachi and Sasuke to go Susanoo, meaning if Obito wants to dodge it he will need to use his MS. Here is where Kabuto ends up gathering intel, once it slips through him. A snakes can fight off Obito, which if Obito absorbs on in Kamui, gains even more intel of Kamui.
Obito having full knowledge doesn't mean he is able to trace Kabuto movements. As once the snakes serve their purpose to attack, he can hide himself with other snakes, as Obito cannot tell which one is the real Kabuto[
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]. So to say Obito is not stopping Kabuto going in SM, as he will fool the Sharingan.
Once Kabuto enters SM and gathers info of how Kamui works, this is when the match begins. As 1. Obito countering White Rage will also give more intel that he is using some S/T to works his jutsus.
That said Kabuto's methods to defeat Obito would be
1. Using SM's nature force around Kabuto to damage Obito. Once Obito uses intangibility, to phase though physical attacks, attempting to take advantage and solidifying to end Kabuto, would lead him to get hit by natural force, since it comes later after the swing[
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].
2. Oral Rebirth[
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].
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.
3. Sound Genjutsu. T
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, so playing constantly is possible to last more then 5 minutes.
4. Kisei Kikai no Jutsu. This invades the body near instantly, shown against Kiba[
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>
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]. The moment Obito attempts to absorb him with Kamui, Kabuto simply enters his body ending the match.