I think it might be a useful exercise to treat the original fingerprint form taken from Sheila's hands, during autopsy, to (a) a fresh hand swab test to check for presence of gun power residue, and lead deposit, (2) use of luminol to check for the presence of blood on the fingerprint impressions of both hands, with a view to resolving the question of whether or not she handled bullets in order to reload the guns ammunition magazine, and also to confirm that there was, or wasn't human blood present upon her fingers, which mixed with the ink used in the fingerprinting process. It may even be scientifically possible to find the DNA of the other victims in the ink impressions of Sheila's fingerprints...