Working from memory, here, but I believe if you click on the handle of the coda sign, you will see the option to hide it.

I would use a Staff List to define which staves show the To Coda or Coda marking in the score and also in the parts.

Tried the category designer but does not allow me to edit coda signs.  I can't find a staff list for coda signs either editing an existing sign or creating a new one.

Clicking on the coda sign handle does not give an option to hide

Yes.  I was trying to edit an existing coda, but if I delete and add a new I can use the staff list to make the  change.