Bases remove protons, not nucleophiles.
However, things seem reasonable so far. What I was getting at before is that normally acetate is a pretty mild base without much hope of attacking that benzyl site. However, activation by the crown increases its basicity by effectively removing potassium from the scene. From there, I believe this reaction has more in common with azo coupling than the von Richter reaction, i.e carbon nucleophile attacking a diazonium. I've no idea if this reaction has a name or not.
Not sure how you're getting a positive charge at the 1-position on the benzene. After the initial deprotonation, the net charge should be neutral. You've also got to go from the 3H-indazole to the 1H-indazole.