Locked out of account

Ok so, my friend account got hacked, he is able to be inside of it still, but unable to change password or recover it since he canno't access his email.

we tried contacting discord support but they just say they cant help unless we use the same email from the account, but there must be onother way to recover the account right? we have so much proof the account belongs to him

like his phone number being there

the hacker sending virus files to people

since he is still able to access the account, it means he can show he still have access to it, meaning he might be the hacker or the owner, he can also say what happened in chat and send the message link.

the devices connected to the account (Before it was hacked and where the most used) he can access those and show proof its their device.

there are even several other accounts (like steam) that are connected to the account, and can be used as proof

if he used the same email for other stuff too, then thats more proof that he had access to that email