Historian Kal Singh Dhindsa raised £1,500 to restore the grave of John "Jack" Kirby.
A battery in a laptop which was disposed of is believed to have caused the blaze.
Derby County's John "Jack" Kirby refused to give the Nazi salute during the club's tour of Germany.
The coins were found in fields in two villages in Derbyshire.
A 35-year-old woman and 25-year-old man have since been released under investigation, police say.
