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No, and I am very disappointed about it.
I looked up that person, and there is no other email than the one provided by him.
I have received no response yet.
Maybe I should send an email to the supervising professor of the so-called 'study', I think that he is also mentioned.

Yeh worth a try. Would be good to sort this out once and for all..

I tried sending a DM on Discord.
No reply yet.

This is my update after finding the user on Discord:
https://peakd.com/hive-167922/@keys-defender/re-keys-defender-s3wdnm