@scat1620 is correct. Both 7DS & Deluxe Escalation challenges are visible to everyone regardless of ownership and count towards your overall completion percentage of each location on the Statistics screen.
So the total number of ‘premium challenges’ currently stands at 22 challenges (15 Deluxe challenges, 7 7DS challenges). Based on there being 7 challenges for the Greed pack, we can assume that there could be a total of around 64 premium challenges once the 7DS is complete.
64 challenges would account for about 16% of the total challenges in Hitman 3. This means that, without purchasing every DLC, you will remain at 84% after completing every challenge available to you.