In the same chapter (PRO-SUP-10), take a look at the Vs - stall speed:
Authorities allow aircraft of the A320 family to use the following factors:
‐ V2 = 1.2 × 0.94 VS1g = 1.13 VS1g
‐ VREF = 1.3 × 0.94 VS1g = 1.23 VS1g
So, VREF is 1.23 VS1g and VREF is VLS in CONF FULL, so VLS is 1.23 VS1g in any configuration with flaps extended except during takeoff.
Don't blame yourself, it's the way Airbus manuals are written.