During a police probe into the distribution of BZP in New Zealand, officers concluded that Robinson was supplying Clint John "Storm" Helmbright with the pills. Helmbright was jailed for 12-and-a-half years in December after being found guilty on a raft of drug dealing charges.
Police seached the shop and warehouse of Hugh Robinson's health food and supplement firm, High Performance Health (HPH), along with his house and car.
Officers found powder or residue in the factory and his car.
They also found a bag containing five smaller bags with a total of 491 BZP pills in his home garage and a bag containing two smaller bags with 100 pills in his office desk drawer.
Police,l without a warrant, also searched a Christchurch storage unit in Robinson's name where they found a firearm, ammunition, and 2287 BZP pills.
Defence counsel Richard Maze argued that Judge Alistair Garland had understated or gave insufficient weight to the importance of the privacy interests regarding the unlawful search of the storage unit.
Judge Garland had admitted the incriminating evidence after finding police had "an objective and credible basis" for thinking there were controlled drugs in the lock-up, and that the search was not deliberate, reckless or the result of bad faith.
But appeal judges found Judge Garland's approach was "orthodox".
In dismissing Robinson's appeal, they were also satisfied that evidence around Robinson's finances, which an expert believed was consistent with money laundering, was also properly admitted by pre-trial Judge Emma Smith.