If it doesn't, is there another accuracy-raisin ability Wide Lens does stack with?
I tested this out with NebbyY (thanks again!), and actually Victory Star does stack with the Wide Lens. I used Focus Blast with Victini, holding a Wide Lens. The accuracy of Focus Blast was 84, which is 70 (Focus Blast’s accuracy) x 1.2, which makes sense because Victory Star and a Wide Lens increase accuracy by 1.1x each.
Victini’s Set
Victini @ Wide Lens Ability: Victory Star EVs: 4 HP / 252 SpA / 252 Spe Timid Nature IVs: 0 Atk - Focus Blast
Hope this helps! :)