The more I go down my rabbit hole...I dont think it was an "intercept" at all, but rather a field test. Think of this: We know the range of the AMG-114 is ~11km. There were two Reapers involved, the view we see is from the "lazing buddy" and the other one fires the missile. Why would two Reapers just so happen to be patrolling within 6 miles of each other and both just so happen to spot the UAP. Then, unprecedentedly, fire upon it! The missile not exploding has got me boggled. Sure, stuff fails, but it looked kind of like it hit a water ballon and just went of screen. But I dont think we were ever meant to see this footage.
Now dont get me wrong, I whole heartedly believe that extra-terrestrial life exists, probably all over the universe. I just dont necessarily believe they are here on Earth. If they are, its the octopuses.