As described, the French lose
Bridging the lack of maps like lightning
Ok, we have pilots that have no suitable airmap. What do they do? They launch some planes and start to map the city at once. As there is no anti-air available for the French, they can fly over the city and make photos. How? Because Paris is well within the 2000 km range of the Germans Ardo AR 235 even if they would launch their recon Aircrafts in eastern Prussia! Assuming they launch in Cologne 400 km away, the French have not one week but 30 minutes before the first recon-bomber is over Notre Dame and will start to map the area. After two hours of uninterrupted photography (again, no anti-air), it turns around and lands 30 minutes later. Two hours after the landing, the High Command is not only in possession of aerial photos of all of Paris, they also are just hours away from having the best map of Paris that ever existed, showing the exact location of Notre Dame and any attempt to cover it up. Making a rough map with the river and the location of all the churches is a manner of hours now. How do they look? Well, this is a REAL aerial photo of 1943:
The next morning the air bombing can and will start, six days ahead of the plans of the Parisians, no longer stopped by lacking maps.
The Anti Air vulnerability
"A week may pass before the first bombers arrive, and anti-air weaponry will be available within two weeks of the first arrivals." - OP
As established already, the one week time to prepare the defense is a vast overestimation by the French and only feasible if the Luftwaffe has some odd lack of bombs available and needs to reroute or acquire extra bombs from other battlefields to crush Paris. Anyway, the Luftwaffe has total air dominance for two to three weeks.
Without an anti-aircraft supplement in place, now there is little to nothing the French can do between Ardo's taking photos and mapping the city and dropping occasional bombs. With the lack of any air defense, once the bombers come, there is nothing to keep the bombers away from the town and use daylight to aid in their bombing. As a result, the bombers come in broad daylight and can use the Seine and other buildings alone to estimate where to bomb to hit the one building they are interested in. See the large park north (Les Jardines des Halles) and the block of houses next to the park (Jardin des Plantes) SE? Notre Dame is where a line south from the park's east side would meet the elongation of the north wall of the university. It's in the elongation of the eastern island's edge between the first and second bridge on the second. Making a good aerial description of the target area is trivial once the photos were made.
Or they could just go to indiscriminate bombing of the inner city islands, leveling everything: Even the most useless map made from tourist photos shows that the cathedral stands on the south-eastern corner of an island, and bombing the whole island into smithereens would surely also hit that area. Hell, even with just tourist guides to guide the pilots, they might fathom a simple map: the guides and history books tell of other related landmarks like the smaller Saint Chapelle (yellow) 440 meters to the East-North-East, right next to the Palais de la Justice (green). And that Notre Dame is directly next to the huge complex of the Hôtel-Dieu de Paris (blue).
And here with more area around to show how distinct the area is:
Disguising or protecting Notre Dame is not an option anymore at this point.
Flipping the Eagle
Having no chance to cover up their Lady, the French have only one option left in the short hours: Deny their enemy the victory of destroying the church by evacuating everything from it they can and then destroying it themselves. There is no chance they can hide or protect an area about 1000 by 300 meters that is - conveniently for air attacks - right in the middle of a river.
Short of leveling the whole island and filling in the river, nothing can permanently disguise the position of Notre Dame. And nothing short of burning Paris to the ground can temporarily cover the whole city in so much smoke that it blocks aerial photography.