After the game Vernon approached Mariota and apologized for the hit. If he meant to hurt him I cannot believe he would seek him out to apologize, he would probably not even acknowledge the incident.
If the shoe was on the other foot, and Ryan Tannehill got hit like this, I can guarantee you every Dolphins fan would be up in arms. There are reports for sports casters that it looks like Vernon slips on the play and now the conspiracy theory is how did he slip to cause him to go forward and hit Mariota?
In my opinion, this is how he slipped. Maybe…just maybe when Olivier Vernon came off his spin move and with the extreme force of planting his foot on the natural GRASS turf (that is the type of field that the Titans use). The actual force of him pushing off that foot caused him to slip and continue forward, which caused him to hit the quarterback low making it impossible for Vernon to stop himself. Yes, I will be going for my degree in forensic science tomorrow.
Either way, Olivier Vernon should expect a call for the league about paying a fine for this incident. I cannot see a suspension coming for this hit, but being that quarterbacks are very well protected a fine is very likely.