Here you go actually, straight from the horse's mouth:
> [Update] It looks as though CDPR bypassed some of the TRC process, promising the platforms it would be fixed for launch, but that doesn’t change the fact that both platforms have a legal responsibility to their consumers to provide a usable product. “In terms of the certification process and the third parties – this is definitely on our side. I can only assume that they trusted that we’re going to fix things upon release, and that obviously did not come together exactly as we had planned,” said Michał Nowakowski at CDPR in a conference call.
The rules are different if you're important enough, I think that is just be expected at this point.
You're right this is about avoiding bad press on Sony (or the need for Sony to revise their return policy), but it's also about Sony as a publisher enforcing their relationship with studios.
Sony's return policy for digital isn't consumer-friendly and something I want to defend, many call it a "no refunds" policy, as if you start the game even once you can't get a refund. But as publisher it's their right, and within their interest, to enforce it. It's not up to studios to unilaterally change it.
On Dec 13th, CPDR issued the tweet/statement, "For copies purchased digitally, please use the refund system of PSN or Xbox respectively."
The next day at an investor call, investors asked them if they had a special refund agreement with Sony and Microsoft. They said they didn't. 
Then the next public statement from either was Sony saying it's removed. The next statement from CPDR was to investors but was leaked, essentially saying they met with Sony and Sony told them it was being removed. Oh, to be a fly on the wall for that meeting.
Microsoft has also said full refunds for anyone who requests, matching Sony.