Established Fact
Where named donors disputed unauthorized charges through their financial institutions, chargeback records held by card networks (Visa, Mastercard) and issuing banks constitute recoverable evidence of confirmed unauthorized use — directly corroborating victim complaints.
Citations
Visa Operating Regulations § 11.2 (chargeback rights)
Mastercard Rules § 13.1
records held by issuing banks and acquirers
subpoena required