If you change every crawling to walking you just temp force fix it , and possibly let even cuffed slaves to walk thus they can escape and wings+flying etc are changed to walking to. The problem seems to be that the cuffed status is permament and slaves keep it even after removing cuffs/equipping different equipment to the same slot and advancing a day . With only a few slaves and small save you possibly can change restrained to none restraints to free , but i can only hardly see wich part of the code goes to wich slave /i have 10+/ so there are possibly some other things that force keep the cuffed status , thus crawling.
edit : needs a bit of testing , but it looks like it changes the movement trait too so even after editing restrains and restrained it still keeps the crawl, i let my eyes rest a bit and try to dig a bit more in the save
edit 2 : Yepp it seems that cuffs set both movement and movement trait to crawling and the 2nd makes it permament . Code seems to show in mod effect settings that the change in both is intended , but maybe there is somethings that should check and change it back if cuffs are removed , but me to find that its a bit too deep.