Yes, it's from the operator of bytefend and they have been sending numerous threatening emails for months.

You can check the statement from the victim Frantech from the link below:

On Tue, Oct 19, 2021 at 9:34 PM Ray Bellis <ray@bellis.me.uk> wrote:

On 19/10/2021 13:29, Travis Garrison wrote:

> Yup, same here

and here.

For now we're just ignoring it, but if anyone wants to quote us (ISC, a
DNS root server operator) in the event of law enforcement action please
let me know.

Ray