Yeah it's definitely tricky... To me the action of the slide is the movement to block the path, even it was for the previous action, I think that action and DLC running into him are close enough together in time to warrant the penalty.It’s only impeding if he moves into his path to block, he doesn’t do that. It’s a tricky one but clearly no intention to foul or block, he’s allowed to try and block the ball himself and defend.
Its 1 of those grey areas but CL is the one that creates the contact, so for me no penalty.
I think that's the what the ref saw too as no red card was shown (as the block of the shot is a clear attempt to play the ball)