spy communication

So the rules state that we cannot use electronic means of communication with the spy. My team has fabricated these concepts to get information from the spy to the drive team. I haven’t found anything in the rules contradicting these ideas, but if anyone has a dissenting opinion, i would appreciate your feedback!

-Signs with symbols
-A whiteboard and marker
-Cup telephones

Your feedback is appreciated. If one is not legal, I would greatly appreciate an explanation as to why.

Thank you for your time!

Using the cup telephone would result in a violation of T26-1–it’s communicating outside of the Castle.

As far as the rest, have at it (within reason).