In one of your pics you have bubbles in the bucket side of the airlock, but most of the liquid in the exit side. Not sure what to make of that. If you had airflow going back into the bucket most of the liquid should be in the bucket side. I've had that happen when I added 100+ degree wort to a fermenter and then put the airlock on before chilling down the rest of the way to pitching temp. Even in that situation, the bucket side of the airlock filled up, but was only the bubble wall's worth of starsan that was actually going back into the fermenter. Now I cover it with foil till it is all the way chilled, so it is just air and no starsan going in, but as others said, that amount of starsan is really nothing anyway.
I first did Hanks "Hefe" (I don't think it technically is a Hefe) as a kit and have done it more times with bulk ingredients; one of my favorites. The fermentation can definitely go on that one. When I have that much starsan in the airlock, about two thirds of it will bubble out quickly, but then the level will almost stop dropping from there. I top it off a little every now and then, but if you fill it up to 3/4 full again, it will bubble out again.
You can use vodka for little or no bubbling, but seems like a waste of money just for airlock media to me. Maybe if you are going out of town and won't be able to check on it for a week.