Adobe blocked my account for a ridiculous reason

Adobe Contributor support is quite responsive to requests send to them. watch your spam folder.

It is also so, that moderation and claims are taken seriously. There is no automatic scanning of any kind and decisions to close down a contributor's account are taken for reason by humans. You an Adobe know that reason and you need to take appropriate action to prove your point. 

It is baseless to continue discussing this here on this user to user forum, as Adobe won't publicly react to legal proceedings. 

As you do not have a question we can answer, I will lock this dicussion now.

Obviously we can't know the details. However, if someone issued a DCMA complaint against you, and you did not respond, this must be (legally) an acknowledgement that the complaint is true. DCMA complaints are raised by humans, who claim to have created a work, not an automated process. No idea if this happened; we really can't do any more than speculate. Adobe will not talk to you about this issue in a public forum, to protect your privacy.

The members of this forum are not Adobe employees, and are unable to answer your question as to why your account was blocked and what means were utilized to identify the videos in question. I don't think Adobe uses any software to scan the internet looking for duplicate copies of the assets that have been submitted to Adobe Stock; however it is possible that a Buyer came across the other videos and reported them to Adobe.

As to your threat to sue Adobe, perhaps you should read the indemnification clause in the Adobe Stock Contributor Agreement.