Nothing, except you will have the PA alignment error from the guiding setup onto the mount.
(Except possibly with OAG)
You will need then to use the GoTo autocenter activated to GoTo, center then plate solve your first target, using main camera and tube so you "void" this misalignment.
Unsure if sync mount will permanently correct these, or you will have to plate-solve / Autocenter each time you slew to a target.
What is your issue with main tube/camera?
