I don't know how accurate this is but in the affidavit Johnny stated that he first became involved with Petro. On October 13, 2008, Teresa Brown approached him while he was in Florida doing his radio show because Heurung had experience with mines and oil and she knew he could bring in good assets.
As far as his background goes I've seen people post that Johnny was doing weekly calls long before he got involved in Petro America Corp promoting different money making opportunities and alternative health options.
I found his name attached to these two health related products online from pre-Petro America Corp.
Back in 2001 - 2002, he was involved with some machine called the PAP-IMI, as the general manager of Bio-Energy services. He seems to have rightfully distanced himself from the machine and it's maker after initially promoting it's powers. Maybe like with PAC he saw legal issues coming and quickly began testifying against others to save his own skin or maybe he came to his senses before the legal action started. I don't know. I hope the later.
Really not sure much about his background besides all that. He had a lot of rumors tied to his name on the forum but nothing I could verify.
Sounds like he has distanced himself from Petro America Corp too and now just talks about his current alternative medicine programs or money making opportunities.