You are working on misinfo here. 1) UEFA had been investigating Palace for breaching rules long before any contact from Forest. As the 7th place club they would be taking Palace’s place. So the the club wrote to UEFA to as for an estimate of when the decision of their investigation would be made.
Given Forest having been caught by FFP before the club wanted to know what budget they would be working with this season. Very different between EL and ECL. Transfer that weren’t already agreed were put on hold until after Palace’s appeal.
2) The multi club ownership rules include being part of a holdings company. Palace were. John Textor’s Eagle Football Holdings. 5 clubs. This included Lyon, which is why Palace fell foul. This was very easy for UEFA to discover through Companies House and their website. And they already had.
To suggest Forest had an involvement in somehow leveraging UEFA via a secret plot is ridiculous. It seems to dismiss an actual breach of the rules. Palace were rightly punished for that. I don’t feel it to be in spirit of the game. But by the book? Rules were broken.