Here's something you might want to try out in the future. Normally, I install cloth end to end then back to the side pocket, starting on one side first, then switch to the other side, do the same thing, then close off my ends. With thick slates and deep cut pockets, after I lay out my cloth, I place a mark on both sides of the side pockets, 7/8" of an inch out from both corners of the side pockets, this is to give me the right amount of slack to finish my side pockets with, without having to fight them. Then, I start with attaching the cloth on both sides of the first side pocket, then stretch the cloth from the side pocket in the direction of both corner pockets. Once I finish the first side, then I go over to the other side, stretch across the table 2 1/4" inches "Simonis 860 & 9ft slate" and attach the cloth first on both sides of the side pocket again, then once again, stretch from the side pocket to both corner pockets again. Once both sides are done, I then go and finish stretching my ends, then finish off all the pockets last.
In the pictures posted, this is a Diamond 9ft Professional 3 piece slate, 1 1/4" thick plus 3/4" backer board for a total of 2" thick. The first 2 pictures are of the side pocket, the next 2 are of the corner pocket. Notice, no staples holding the cloth to the backer boards as I installed this cloth using my gluing method, but there are staples in the pockets, you just don't see them.
Glen