"I've had injuries, and i've never asked for help. And the one time i need help, it's pretty much goodbye," says Mr McKenna.
A respiratory specialist declared him unfit for work. But ACC's occupational physician said he could work.
However Paul's case is not out of the ordinary, his advocate sees hundreds of people specifically about problems with ACC.
"I do see a lot of vulnerable people that have no idea where to turn after a decision like this has been made," says advocate Mike Kletzkin.
Mr Kletzkin became an advocate after having issues with ACC himself years ago.
"I've been in business since 2005. If there wasn't a need or if mistakes weren't being made I wouldn't be here," says Mr Kletzkin.
But for Mr McKenna one thing keeps him going.
"I've had times where the only thing that's kept me going is my dogs. Otherwise I would have topped myself," says Mr McKenna.
An ACC spokesman said there was no plan "at this stage to suspend" McKenna's entitlements.
"ACC believes it has followed the required processes in a timely manner and maintained good communication throughout the vocational rehabilitation process, the review process, and the post-review process.
"We believe we have treated Mr McKenna respectfully."