DUP special adviser Andrew Crawford assured Moy Park that there would be no reduction in the Renewable Heat Incentive's (RHI) lucrative tariffs more than six months ahead of a scheduled review.
The one-time adviser to former Enterprise Minister Arlene Foster also told the inquiry into the botched green energy scheme that at the time he was unaware of any link between the poultry processor's rapid expansion and the RHI's generous subsidies.
Mr Crawford speculated that he became aware of a relationship between the surge in Moy Park suppliers and the RHI scheme in "springtime 2015".
However, inquiry junior counsel Joseph Aiken went on to highlight correspondence from autumn 2014 between the DUP spad and Brian Gibson of Moy Park, whom Mr Crawford said he had been friendly with for many years.
Mrs Foster's adviser shared a one-page fact sheet via email with Mr Gibson, who the inquiry heard was one of poultry processor's "lead people". Mr Crawford claimed the information on the internal briefing document was already in the public domain, however, in the accompanying email he assured the Moy Park representative that there would be no reduction in the RHI's generous tariff.
He said any potential changes to how the scheme operated outlined in the department document were "unlikely to have any negative impact on Moy Park growers".
Inquiry panel member Keith MacLean said he could not see anything in the email that would enable him to conclude that the changes were not likely to have a negative impact on Moy Park.
He asked Mr Crawford what additional information he had at the time that led him to provide Mr Gibson with such an assurance.
The former DUP spad said he would make a distinction between Moy Park and the company's suppliers.
"Growers for Moy Park were already on the scheme and because of grandfathering their tariffs were unlikely to change," he said.
But when pressed by Mr MacLean on how he was able to make such an assertion more than six months before a review, Mr Crawford said he was unable to say "exactly what I was referring to in that particular point".
Mr Crawford said he was only replying to a query that could help the company but inquiry chairman Sir Patrick Coghlin insisted that Moy Park was not entitled to "insider information".
The former spad went on to tell the inquiry that he regretted not picking up the warning sings about the RHI scheme's flaws and claimed that if he had been aware he would have been able to implement cost control measures.
"This was very much a new industry in that it was a new scheme and how it was being used to support businesses," he said.
Mr MacLean noted that there were "plenty of people who picked up how lucrative it was".
