Disputing copyright claims on YouTube and need to know if my permission agreement form is useable.

LOCATION: AUSTRALIA/YOUTUBE VIDEO My agreement form that people submit videos to my channel with has gotten copyright claims released on videos in the past but dealing with this one licensing company, they are refusing to release the claim on the grounds that the person who sent in the footage was a minor and I didn't have their legal guardian/parent sign off.

I have amended my form to include this factor at the end but am wondering if this licensing company is trolling me or they are in fact correct. I was sent the video a month prior to them purchasing it.