Is the Jackson estate paying Paul Anka for nothing?

Much has been made during the last few days of the fact that the new Michael Jackson single was actually a collaborative effort with Paul Anka. The 'My Way' singer claims that he and Jackson worked together on the song in 1983 with a working title of 'I Never Heard'. The single was released by an obscure artist called Safire in 1991 with Jackson and Anka listed as co-writers.

But all may not be as it seems.

Information held by the American Copyright Association suggests that in 1980 Jackson wrote and recorded a demo called 'This Is It'. The ACA lists the track as follows:

So it would seem that although Jackson and Anka may have tweaked the song at a later date, there was an existing demo which was exclusively written and recorded by Michael Jackson.

The question is, is the new single Jackson's solo demo or is it his Anka collaboration?

It seems to me to be the former.

Listen carefully to the new single. Several lines seem not to have any lyrics, Jackson instead scatting gibberish - placeholder vocals - to plot out the melody of the song. However, the 1991 Safire release - co-written by Jackson and Anka - boasts completed lyrics.

Has the Jackson estate just agreed to pay Paul Anka 50% of the profits for a demo in which he had no involvement?