But it explicitly shows that it's using Minio when the application is actually used?
Sure, it's totally uncool to not mention Minio on their site and that's a massive shame but, as far as I'm aware, nothing in the license would require Weka to explicitly mention they're using Minio in their advertising/marketing like the provided link?
Making money off from another product calling it your own innovation is plagiarism.
https://www.weka.io/blog/cloud-storage/amazon-s3-protocol/
There is never a mention of that it uses MinIO underneath.