Well I hate to break it to you, but the Dronezone is where my COA's (Certificates of Authorizations) are located and that the paperwork says to call ATC to get authorization. Thanks for your input even if it is incorrect.
Then your original post (below) was misleading. This thread was about recreational pilots calling towers/airports as required by Part 101. So, I'm not sure why you even posted about Part 107 arrangements, but you appeared to be saying that under Part 107, without LAANC, you simply call local ATC rather than use the portal. And when I pointed out that you should use the portal you didn't mention that you had already done that, and that the waiver/authorization simply required you to call ATC as one of its conditions.
As a 107 operator in a town without LAANC and required COAs in Class D, I have to contact ATC everytime I want to fly in controlled airspace. If I am going to fly around the Capitol building, I notify the Capitol Police Dispatch as well to stop any LEO interruptions; and if in the vicinity of the hospitals, I contact LifeStar dispatch.