The 49-year-old father of three was killed on Saturday afternoon when his motorcycle collided head-on with a van on the Crown Range Rd.
Mr Middendorf was travelling towards Wanaka as part of a motorcycle rally when the accident occurred about 5km below the Crown Range summit.
Senior Constable Bruce McLean, of Wanaka, said a female doctor visiting the area was on the scene within minutes of the crash and provided medical assistance to Mr Middendorf, but was unable to save him.
While police inquiries were continuing he said witness reports indicated Mr Middendorf had been on the wrong side of the road at the time of the collision, which closed the road for about two hours, diverting traffic via State Highway 6, past Cromwell.
A statement released by Mr Middendorf's wife, Judith, and daughters Charlotte, Korrie and Whitney to the Otago Daily Times yesterday said he had lived his life ''to the full''.
''He was loved, respected and admired by his extended family and by many in the community.
''Family was a top priority for Tony ... We miss him dreadfully.''
AJ Hackett Bungy co-founder and director Henry van Asch said staff were informed of Mr Middendorf's death yesterday morning and were ''distraught''.
Operations were suspended for a time yesterday.
Mr van Asch described Mr Middendorf as ''an absolutely fantastic guy'' who was ''loyal, trusted, respected and loved''.
''He was just a huge part of the organisation.''
Mr Middendorf would have celebrated his 20th anniversary with the company in February.
Mr Mittendorf, who was born and raised in Queenstown, was initially employed as a mechanic and boat driver and worked his way through the ranks, eventually training jump masters and overseeing operations for all of the company's Queenstown sites.
''He's just a guy who always surprised me with his resilience and passion to achieve and adapt,'' Mr van Asch said.
''He [was] one of the most core parts, one of the most key people in the team. As far as the management team goes, they're all devastated.''
On a personal level, Mr van Asch said Mr Middendorf was down-to-earth and humble with a fantastic sense of humour, who had long loved motorcycles and was an experienced rider.
''He loved Pink Floyd, Led Zeppelin ... he normally wore a Pink Floyd or Led Zeppelin T-shirt to work.
''[He] loved skiing, mountain biking; loved his engines, whether they were in boats, cars or bikes.
''He was always very proud of his current mullet [and] at the bungy parties he was always the life of the party, dressing up in whatever ... he could get his hands on.
''He's going to leave a huge gap ... I'm going to miss him as one of my most trusted, long-serving deputies.''
He said the company was offering the family support.
