CH Robinson, though, just lost a lawsuit at the Supreme Court with similar premises. They are a freight forwarder and third-party logistics outfit that contracts large amounts of capacity with subcontractors (airlines, trucking companies, shipping lines, etc.) and sells a complete package to their clients.

One of CHR's service providers was conducting hiring shenanigans and not fully, legally screening their drivers. One of the service provider's drivers hit another vehicle and crippled that vehicle's driver, who sued. CHR argued all liability should fall on the trucking company who hired the driver. The Supreme Court said no, CHR could be held liable for negligence in vetting their service provider as well, because it was ultimately CHR's load being carried.

I'm not a lawyer, but under that legal precedent, it seems Amazon might not be off the hook for damages in this case, given it was their subcontractor who was carrying Amazon cargo in a jet with "Prime Air" on the side.