I worked out the troublemaker, unfortunately I don;t see a way around it. I have this:
https://www.ebay.com/itm/Flexi…i-computers-/333301477068
To move my TF536 over a few inches (using plastic standoffs so it doesn't make contact with the board. I have this because I have a megachip coming in the mail in a few days and the above flexible rellocator is the only way I can move the TF536 so it will clear the taller Agnus stack. So it seems I may need to decide between mega-chip, TF536 or Indivision... I apparently cannot have them all because the indivision doesn't play nicely with the flexible processor extender.
The rellocator does work fine with standard Denise though... maybe s-video will just have to be good enough.