Unless...
Tony,
I have looked at the pictures posted again, and you would appear to be right... again! The three ships you mention as doubling the French line are indeed British, even though I can't clearly see the Union Jack which, as you suggest, is probably more clearly visible to you and Ed! The more obvious fact that they have their sails (seemingly topsails only) set I completely missed and which, more than any flag, would have suggested they were not French!

(I don't think any of the French ships would have had their sails set at anchor!) However, why then are these three ships seemingly on the outside of the French line, whereas the majority of the British fleet are on the inside and passing between the enemy and the shore? This is surely the opposite of the case. Is this another instance of Davison/Boulton and co. being mistaken? It also seems to me that the Vanguard (if that is her in the foreground, which seems likely) could still have occupied the centre of the scene, if the ships had been depicted correctly, i.e. going to the left. Nelson's flagship was overtaken by those following her, who then anchored by the stern and were thus strung out ahead of the Vanguard, and as shown on the right on the medal. However, they too would then very likely have had their sails furled...

As you say, one can rather more forgive the 'production company' back at home, who presumably had various officers' (conflicting?) reports of the scene to go on and who, also presumably, had not been anywhere near Aboukir Bay! Similarly I agree with you over the Union Jack v. the ensign and its depiction.
Knight's diagram, which I agree would indicate that the French fleet anchored by both bow and stern is not, I think, the only such mention of it, but it would not seem right (and, as you say, it is corrected in his text) since the British themselves (or at least Foley) picked up on the fact that they were at single anchor and thus could swing and allow the British to pass. Hence the action by the five British ships that followed and which was pivotal (sorry) to the battle.
The depiction of the battle (or any sea battle come to that) would obviously have taxed the skill of the engraver to the limit and that, I assume, is why the British ships appear to be under topsails alone! Ships habitually furled their courses in action, but it would have certainly been easier not to have shown any other sails from a production point of view!
Thanks for the information regarding Nathaniel Kinsman's Minotaur medal, as I had been meaning to ask about that!
I have a feeling you might like to come back on this...
