But Sir Stuart Etherington, chairman of the Patron's Fund, the charity which benefited from the lunch and distributed its profits to good causes, described the fee as 'reasonable'.
He insisted Mr Phillips and SEL UK had not 'profited' from the event but was instead remunerated for organising the event and securing sponsorship.
He said: 'On the SEL fee, it was important to the trustees this was undertaken on a non-profit basis.
'We benchmarked the costs at a higher level than the fee so SEL were not, in our view, securing a profit. Indeed the trustees had a legal agreement that no profit would be made on the contract, so we think the fee is reasonable.'
Sir Stuart also said the publicly available accounts reflected 'only part of the story', as several additional donations means the final amount given to charity as a result of the event will rise to £780,000.
'These accounts are yet to be audited and once all funds available for distribution are dispensed, the charity will close and its accounts will be filed,' he added.
Buckingham Palace said: 'The Patron's Lunch was an enjoyable and celebratory event which has directly benefited a large number of Her Majesty's charities.
'Questions about the organisation and financial management are rightly a matter for The Patron's Fund Board of Trustees.'
