Unfortunately, how and what to seal a wound with is hotly debated. Never have read of super glue being used but also haven't read about it being bad.
Personally, I use this to help my oak trees keep away the nasty oak wilt.
I'd recommend treating with some antifungal like neem oil and then using pruning sealant spray and then mending it with twine and or thin cardboard wrapped around it with twine.