Lincoln Castle events - Find a freedom of information request

I am in the process of compiling a list of concerts I have attended over the past 40 years and hope that you will be able to fill in at least one of the gaps.

I have a diary entry showing a concert at Lincoln Castle on 4 August 2000.

I believe that it was the Animals, Dr Feelgood and Nine Below Zero.

I will be very grateful if you can confirm that, or if the date is incorrect the correct one. If the listings you hold is in spreadsheet or document form I would be extremely grateful for a copy, if they are in the public domain, from 1969,

Lincoln Castle does not hold records of events going back this far, however looking at an unofficial webpage does suggest that Dr Feelgood played in Lincoln on October 20th that year, however it was at The Lawns, not Lincoln Castle.