The clock operator botched the final play, but I think the timing was correct.
On first play officials called maye oob. They were wrong, and replay fixed it. The rule there is either 10 sec runoff or spend a TO, t simulate what would have happened if they ran a play with a running clock. The 10 sec runoff is from when knees were down, not from when he was called oob. I amagine they looked at the clock and saw 16 sec when his knee touched down, then ran off 10 sec so final play started with 6 sec.
On the second play, clock never started. I guess the play was 4-5 sec, so letting the FG attemp go was the right call.
They always say official time is kept by some secret referee on the field. I think it would be tough for an official to watch player for fouls and keep time, but that’s what the nfl says.