You do not need to get the lable wet at all.
Just allow the LP to lay flat and drip the solution into the grooves. It will stay in the groove area. Just keep it from drying up while soaking
The one point you might get some water on the label is when you pick it up and tilt it to go into the spin clean. Just have a paper towel ready to keep the label dry.
(at least half the labels are actually waterproof, most are somewhat water resistant. only a few really are water, die instantly..)