GM Note: This message arrives on Mehras 4th, and yes a finger was included in the wax sealed message.
This finger of your servant should serve to convince you of our seriousness regarding this message, warning, your choice. You have 3 days to board passage for your capital of Tristine. You will get further instructions about what you and the Blood Inspector are to acquire from The Archive, and trade for their lives.
Picture of finger from EBay.