It urges New Zealand ministers to "help us navigate through this difficult time" by "working with the Chinese Government to remove this new testing requirement".
Two months later while on an official visit to China, Ms Collins dined in Beijing with Ms Xu, Mr Shi and the senior border official who she still refuses to name.
NZ First Leader Winston Peters said the letter and other documents showed "two Cabinet ministers rushed to do exactly as Oravida asked, including obtaining taxpayer funds to get special help for Ms Collins' husband's company".
Ms Collins' husband, David Wong Tung, serves on Oravida's board.
Mr Peters said other Kiwi firms faced the same problems as Oravida after the botulism scare, "but they did not get this same level of help".
He said it was time Prime Minister John Key "took action" over the affair, "unless he places more value on the political donations the National Party receives from Oravida".
Oravida donated $56,000 to National in 2011.
In Parliament yesterday, Mr Peters asked Ms Collins: "Does she not understand that her arranged meeting with that official was a serious conflict of interest and a corrupt abuse of her Cabinet position?"
Ms Collins, who has been increasingly defiant about the matter in recent days, lashed out at Mr Peters and his long-time partner Jan Trotman, a former pharmaceuticals industry executive. "I would say to that member that if he is worrying about corruption, I think he should consider a Member of Parliament who asks questions in this House and written questions to help his girlfriend in her position with a major global company."
Blogger Cameron Slater, a friend of Ms Collins, recently compiled a series of parliamentary questions asked by Mr Peters between 2001 and 2007 about issues around Pharmac funding of drugs produced by Ms Trotman's former company. But Mr Peters dismissed the suggestion he'd asked those questions to benefit Ms Trotman's business.
Ms Trotman said Ms Collins' attempt to drag her into the affair was "offensive and disgraceful".
But the exchange in Parliament took some heat off Mr Key, whose picture was used by Oravida to promote its scampi in a recent Chinese magazine ad. Mr Key said the ad "wasn't promoting or endorsing the product".