Massive oil leaks.

i would bet my *** it's a loose oil filter or they forgot the o-ring on the oil filter.

it's an actual leak. if it was crankcase it would be mostly on that one side with the breather. but it's up front the fan is blowing it everywhere.

so if you are positive it's actually motor oil not trans fluid or pwr steering fluid, then i'll bet oil filter.

p.s. when they dyno an engine they run it for like 15 minutes to break in the cam before they test the power. better check that "only 10 seconds" idea you have with the builder. so it was run at least 15 minutes and run at power as well so if it was a breather leak he would have seen it.

the oil filter... could have got bumped or you changed it and didnt put oil on the o-ring or something. o-ring could be off track.