Nah, diesel gate was 2009. The idea for supplying engines to F1 was after Porsche retired from LMP1 in 2017 or 2018. Afaik the idea was to substitute LMP1 for the outrageous costs involved(despite their 3 consecutive world titles) and put the effort into building F1 engines.

You are right, I was thinking about the volkswagen project to join F1 around 2010.