Personally............ I just can't imagine that the two would have power-washed the blood from the truck while INside the hangar. Maybe I am mistaken, but if it were me, I would be very fearful that the red staining would be terribly difficult to get out of a concrete floor. From pics I have seen of the hangar, it seems very clean, almost pristine.. although that would be difficult I suppose, if there were engines being taken apart and such in there?
Even if the concrete floors of the hangar were polished, there could be little nicks and grooves where blood would surely collect and be hard to remove/notice? Can you imagine AJ and SS coming in on the Wednesday and finding pink concrete floors, along with a truck looking like one that was plastered all over the news?
If they power-washed the interior of the truck, which I'm sure they must have, based on the blood evidence, where did they do it? It would have had to have a good strong water supply, I would imagine, for the pressure to be any good? And I suppose if they had a gas pressure washer, they would not have required electricity. Could they have done it at the farm? It would obviously be on well water, but would well water withstand that type of use?
The blood that was found in that little screwhole in the floor of the truck... they did not mention whether it was mixed with water/soap... would it still have been possible to get a good DNA sample from it if it had been watered down with a pressure washer?