Ann: Shell Oil Discovery Offshore Namibia On-Trend to PCL PEL 87, page-134

Not necessarily lying, but perhaps being overly-optimistic.

The first link here is to a Serica presentation. See slide 6, which summarises exploration history. It reports Moosehead Aptian source rock as immature. There are many more examples of this immature/marginally mature analysis for Moosehead-1. https://www.serica-energy.com/downloads/presentations/PETEX%20Tues_18th_Nov_2014.pdf

The second link is to a 2018 PCL presentation where they state Moosehead-1 Aptian is early mature. Somehow they've gone from this to fully mature. Slide 8 in that presentation shows some promise where it shows the source rock depth is greater below where Saturn prospect would be. However this shows a depth map (no labels mind you) with a direct correlation between depth and maturity. It appears to me they have not taken water depth into account (shallows to the east), so I am sceptical of the maturity/temperature contours here. In any case, I am somewhat comfortable that the Saturn complex may be marginally to very early mature, but if that is the case then there may not have been enough oil expelled from the underlying source rock to fill up much of Saturn.
http://clients2.weblink.com.au/news/pdf_2%5C02059698.pdf

Just my opinion.