I'm sure there's a PokeBall, but how do you get in?
Compare the maps. Torment (TM41) isn't located in a gated area. It is located up stairs toward the upper left. If you need the gated area, the upper map should help guide you.
As you leave castelia city towards route 4 there is a hiker and a gap in the white fence go throufh there a travel north then you will see a parasol lady the tm is up then but there are trainers in the way.
Hope this helps :)