Disguises, good point but how would Orochimaru know a password which would have been defended with a lot of security ? It would take too much effort and might blow Orochimaru's plans if anyone found out Orochimaru's spies doing detective work. However if he got the password from Anko, then no effort is needed. The split conscious thing is a secret that no one knew until Orochimaru revealed it. Even better Anko will never know that she was being used by Orochimaru.
No, the Split Conscious is the Original Orochimaru. This is not a clone type technique. It is more alike to a Horcrux where you separate your own self into different parts. And if you do this then you will have a mental or spiritual link to that piece of your being similar to how Voldemort had a connection with his Horcruxes. I mean we saw how that piece of Orochimaru's conscious within Anko became a full fledged Orochimaru Character. Plot Twist : A massive amount of Orochimaru's power is actually sealed in the Totsuka Sword. So, If Orochimaru wants to become a perfect being, a major key is Itachi himself.
So, I think there is a strong possibility that The Split Conscious can relay information to Orochimaru no matter how far or near.
The Curse Seals were confirmed to use Natural Energy or Sage Mode. This means that the Second Stage of a Curse Seal is akin to a Sage Mode. So, if Mitsuki has Sage Mode, considering how close he is to Orochimaru, it is a high possibility that he has a curse seal.
Boruto and Kawaki's hypothetical curse seals are perhaps a foreshadowing that Mitsuki has a curse seal also :
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I remember linking this thread to you a few times have you read it ?
The Demon :
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