Forget the possible tip. The clock didn't start until AFTER the ball left Lee's hand. That's what the announcers and, most importantly, the refs failed to notice or look at.
The rule is clear. With .3 or less remaining, only a tip can count. Lee caught the ball then temporarily possessed it in an effort to redirect the ball into the hoop on his reverse layup. That ladies and gentlemen constitutes a 'shooting motion'. The very reason the NBA instituted the .3 rule is to take clock operator error out of the equation.
Technically, had the pass been more accurate, Lee couldn't have even scored on an uncontested alley oop dunk according to the rule. Doing so would have meant gaining temporary possession of the ball on the catch and control, which makes the play invalid because it takes longer than .3 to execute. Only a redirect tip - which doesn't involve gaining temporary possession - is supposed to be permitted.
The Kings should most definitely win this appeal if the NBA follows their own rule.
Watch the replay in slow motion. Lee releases the ball before the clock starts. The clock operator made an error and the .3 rule is supposed to rectify it.