Extra noises of the all the search and rescue assets in the vicinity and the natural biases of the human operators to want to decipher patterns from the background noises = false positives. There's precedent for that:
https://www.forces.net/usa/banging-sounds-heard-during-search-sunken-us-submarine-uss-thresher
Knowing that the information is in the article you are commenting on.... Yeah I do