Need DNA from a valid source, preferably from the exhumed by by an independent Tech. Must match traces on bullet. If not, stop right there. If a match, then provenance of bullet by metallurgy and then record of facts as to who had what firearms on seen. If any non match, it’s not evidence as to who may have fired it....
Might be a coroner’s report of the extraction of the bullet with sufficient provenance, if it was made available early to Israeli and/or American readers. I wouldn’t bet on it. They’re of the claim-and-then-make-the-proof school of evidence, so popular in Washington these days.