I say the team is experiencing a mid season slump. Free fall would be three losses with a gap of 10+ points each time. KC was a catastrophic show of nothing, but they won the Atlanta game like they should have against a bad team.
Now this Raiders game was like a shot in your own knee, they only beat themselves. But even with a horrendous performance and some bad ref calls they stayed within three points of the Raiders. Says more about how bad LV is though than anything about our qualities.
Bottom line, no, they aren't in a free fall. They just found a way to piss every supporter off by going from top contender to mediocre. 500 team within a month.
And yes, even the injuries and bad ref calls combined are no excuse. I still hope they get back that early season spirit.