I think we interacted on a previous thread where I shared with you my affinity for this training philosophy, but for the sake of anyone else who's interested I'll offer that this kind of training works well for me and checks a lot of the boxes in terms of what I think powerlifting programming should try to do.
Surovetsky is an old man and does not speak English, nor does he have much of an internet presence or interest in promulgating his methods widely. He works with his own athletes and has coached several international level lifters, including at least one former IPF world champion. His methodology is better known in Russia.
Over time, I've managed to gather and piece together a good deal of information about his training philosophy and to the three or four people in the Western world who may be interested, can probably answer most basic questions about how to train this way if you want to give it a shot.
As for the OP question about accessory work, AS is adamant that 1. you don't need to do any unless there is a glaring weakness, and 2. it should be tailored to your weakness, or at least based on a need that is easily articulable. He also insists accessory work be done to tolerance; basically do what you want but don't push too hard or make a big deal out of it. 3-4x6-8 for most accessory work, whenever you want, but feel free to skip it.
One thing you can do is some lat work at every session if you have time/inclination. Otherwise, you're looking at bodybuilding-type work for whatever muscle groups you think need it. In terms of big assistance like front squats, closegrip benches, etc., he emphasizes that if you include this, you'll need to modify the base work to account for it. I wouldn't mess around with the plans unless you have some experience and already know what you're doing.
Curious OP, which programming of his have you seen? I'm pretty sure I've seen everything he's released publicly, but you never know.