Concur. Tai, we'll adjust and split into two categories.
No, there are no rules re: indoor vs. outdoor
Please submit video evidence so we can confirm. Huzzah, Dubbo!
We've been down this road before. Find a YouTube video that show him dunking and share it, please. None exist.
For what it's worth, there's no online evidence that Guinness ever confirmed Bichler's attempt. We at RecordSetter have yet to see any evidence of his attempt. Rick Hessler's record still stands. Read more here: http://www.statesmanjournal.com/story/life/2014/05/21/unofficially-balloon-artist-pops-world-record/9392861/