Mr Williams and Porky stood patiently in line at the council before being told Mrs Chadwick and council chief executive Geoff Williams were unavailable to meet with them.
Mr Williams said he was disappointed Mrs Chadwick did not come downstairs from her office to accept the award, instead it was presented to a rather bemused customer services manager.
"What drew our attention to it was comments coming out of the council that it didn't matter because it was not ratepayer money.
"[The council] should be stewards for good spending of public money...the fact Rotorua's mayor is so unapologetic is deeply concerning," he said.
"The whole reason Rotorua Lakes Council received a tourism grant from MBIE was to promote Rotorua and its mud as a destination. Instead, these geniuses flew to Korea and used the money to buy the foreign variety.
"We elect politicians to be guardians of the ratepayer and taxpayer purse. Unfortunately, that's clearly not happening here in Rotorua."
Supporting Mr Williams was Rotorua District Residents and Ratepayers Association secretary Reynold Macpherson.
"Our members are appalled at yet another example of extravagant and foolish spending, it's [the award] just the sort of publicity Rotorua does not need.
"The problem with mud is that it sticks," he said.
Councillor Rob Kent said the first he had heard of the mud deal was in the media.
"The question has to be asked, 'haven't we got better things to spend that money on to promote the festival', it's like shipping coal to Newcastle.
"But, it's a done deal, we councillors were not in the loop at all and I'd love to know who had the authority to spend it," Mr Kent said.
Mrs Chadwick said the council approved the mud festival two years ago and central government, through its major events development fund, "also decided to invest in an event that is expected to bring tourism benefits and potential trade opportunities".
"Part of our reciprocal arrangement with the Boryeong festival in South Korea is having a Boryeong component within the Rotorua event, featuring their mud.
"The cost of importing the cosmetic grade mud, which will come in powder form, will come out of the overall festival budget which will also include funding from other sources including sponsorship and ticketing.
"The expectation is that the festival becomes self-sufficient over time," she said.
Rotorua MP Todd McClay said he was not aware of detailed spending plans for the festival and referred further questions to colleagues at the ministry.
The inaugural Mudtopia Festival will be held at Arawa Park Racecourse this December.
News of the spending has even been reported by the BBC in the United Kingdom.
Muddy waters
Rotorua Lakes Council agreed to buy $90,000 worth of mud from South Korea.
It will be used as part of an interactive display at the upcoming Mudtopia festival
$1.5 million, spread over five years, and was granted by the Ministry of Business, Innovation and Employment's major events development fund.