Using Dave Taylor’s excellent work on the trial, we find that Joseph “Peanut John” Burroughs was called to testify on May 16, 1865 and again on May 22, 1865.
As far as I know there are no known photos of Joseph "Peanut John" Burroughs, John Lloyd, or Washington policeman John F. Parker. Another person of whom there is apparently no photo is William Petersen. I have seen an artist's sketch of him but never a photo.