The 2GIG panel’s walk test mode and running the magnet down the side of the panel are unrelated.
Holding a magnet to the side of the panel puts the 2GIG motion detector in test mode so that you can test whether the motion detector effectively covers the area you want it to cover. After putting the motion detector in test mode you just walk around the room and verify that it’s LED lights up for all the critical locations in the room. It’s an isolated test of the motion detection itself.
Putting the 2GIG panel in walk test mode is for an end-to-end test that the motion detector is working properly with the 2GIG panel. You don’t need to run a magnet down the side of the motion detector for that. Just leave the room long enough for the motion detector to reset itself before running that test.