"Or a reaction could have led to a TMO referral, a red card for Lee and a try bonus point?"

Perhaps, but IMO, doubtful, as I am sure the incident was reported to the ref, by the Connacht players at the time and would have been checked by the TMO at the time and for whatever reason, he saw fit not to penalise him.
It doesn't often happen that if you lash out at an opponent that you will stay on the pitch and your opponent who you just punched gets a card - no matter what the circumstances.
I think Fainga did the right thing, and has to be praised. If he had struck out, every decision on the matter from that moment, was out of his control.

Or a reaction could have led to a TMO referral, a red card for Lee and a try bonus point?

I see the maximum punishment of 26 weeks was reduced to 13 weeks for previous good behaviour, but then re-adjusted so that he misses 13 games, meaning the suspension is actually 5 months. Good to see proper punishment being dished out for this.

Fainga showed fantastic self control, if he had reacted and lashed out he would have had at least a yellow card.
At the time scores were level and game could have gone either way, and if we went a man down there was a good chance we'd have lost that game.
It looks a sly calculated action to get a violent reaction and a card for an opposition player.
Can't praise Fainga enough, by not taking the bait, he arguably won us the game.
Thought he also had a great game and put in a lot of work

He got the maximum reduction of 50% for apologising (and clean disciplinary record)

there could have been some sort of mercy shown to him if he'd made any sort of attempt to apologise to Fainga'a and Connacht in general, as it was his apology is empty and meaningless.

The way he did it showed he did it on purpose, which makes me feel that he done this vulgar act before and got away with it. Absolutely disgusting, and I think that he should have a financial fine also, as it brings the values of the game down.

Coby done well not to take his head off.

"Not that type of person" is such nonsense. The fact he felt he could get away with it says a lot about him.

www.the42.ie/nico-lee-13-weeks-ban-nose-4503912-Feb2019/

Horrible.

I see Nico Lee of the Cheetahs has been suspended for 13 weeks after being cited for venting the contents of his nose into Colby Fainga'a's face at a ruck in last Saturday night's game. The guy then does a Twitter apology apologising to everyone (the League, my teammates, my club the Cheetahs) except to Colby himself, the guy he actually assaulted.

Knob.