“ I would also plead the 5th.”
This is an easy one. When you ask a prosecutor if he BROKE THE LAW investigating the person he is prosecuting, the answer had better be NO!
Stupidity abounds.
Publicly stating such an opinion whether it is off the top of your head or out of your "back pocket" discredits you.
It reasonably appears from your post that you would advise a witness accompanied by an attorney while offering sworn testimony to ignore that attorney's counsel.
It is your advice that many would find to be stupid.