Sorry for the paywalled article, I couldn't find anything else. Here's a quote:
[First paragraph is just context of the prior allegations]

In a lengthy update to its post from July 29th (embedded at the bottom), it said:

We got this wrong. We’ve completed a full review and confirmed that Suno Studio was used to regenerate the original track. We shared inaccurate information, and we’re truly sorry … We do not support AI-generated music, and our process will reflect that going forward. We’ll require our employees and creative partners to disclose any use of generative AI, and we’ll more closely review everything we put into the world.

The post also apologizes for heavy-handed comment moderation, which saw posts from critics deleted and those users blocked. Rather than issue a new statement, it appears the company simply edited its original post five days ago, 10 days after it was originally posted.

The original video was a demo for a new set of strings designed for extended-range guitars and low tunings. People immediately flagged the recording as suspicious. Things only got worse when D’Addario posted a clip of what it said were the Logic recording sessions of the demo track in question.