VLS isn't important in Pak's (or submarines in general) case. VLS can increase the range but most of what Pak intends to hit is already or will be in range of the weapons launched from the horizontal tubes. VLS can also add the "noisiness" of a sub, increase drag in some cases, increase noise due to more moving parts etc...Attack submarine are better off with just tubes, navies don't use vls for attacking other ships or subs. Vertical multi-purpose tubes can assist in specops but i doubt the navy wants to use the subs as such.
However what's more important is what/where Pak wants as its stern/planes/tail design/blade design/rudder height/location of sonars/propulsion etc...Those questions aren't being asked and i'm afraid the navy, again, will end up with a last generation piece of machine ala f22p.