Hmm. some very dodgy overtaking of the GT cars this year.
LMPs used to just drive round them off the racing line but it seems this year their setup hasn't afforded them enough grip to do that so they're just barging through with the inevitable consequences. 
I'd say the first crash was 50/50 and a racing incident.
Second one though the fault lies solely with the Ferrari imho. How could he not see that Audi?!
Depends, IMHO. :-/ Yes, he would undoubtedly know he was behind but could he be sure how far behind, how fast he was closing and which side he was going round? Not sure.
Slower cars are briefed to stay on the racing line, not to yield in any way to overtaking cars. The faster cars in theory should have enough in hand to pass them off the racing line, and on the occasions I've been they have had a staggering advantage in grip. A GT car can be negotiating a chicane on the ragged edge and an LMP will just drive round it like it was parked.
The footage didn't show a wide enough view to say for sure, but what if the Ferrari was following the racing line as he moved over? The LMP dived into a gap that was predictably going to be full of Ferrari very shortly.
The LMPs have had their power restricted to slow them up. I suspect that it has meant they are taking bigger risks to pass the GT cars. Unintended consequences...?