Low value angle but still sketchy

$2/$5 table, button is in seat 8. Seat 9 is small blind, seat 1 big blind. Seat 2 straddles for $10. A bunch of limps mixed in with a few folds. Button folds. Small blind limps, big blind throws in an extra $5 to call. Straddle checks. 5 or 6 players to the flop. $50 or $60 in the pot.

I put out the flop.

I start to rearrange my rack (the previous dealer left it a mess), but I am carefully watching the player on seat 9 waiting for him to act first. To the best of my knowledge he hasn't moved. I continue with my rack, while watching him.

Then out of the corner of my eye, I see seat 4 check. I perk up, and say "Stop the action". I ask seat 9 if he has acted yet.? He does not answer me. He continues to look at everyone else to see what they are doing. Meanwhile, every other player in the hand checks (nobody stoppedthe action). Then the player in seat 9 speaks up and says that he hasn't acted yet and throws out $15. I pause for a second, and start to speak up and say that he didn't protect his action and it has checked around. I barely get the first syllable of the first word out of my mouth after the pause but it is already too late. Everyone else folds.

It is one of those hands that no one was really interested in. It was a small pot, obviously Everyone missed, they were just more interested in getting back to their phones or their conversations with the neighbors, that they just blondly acted after their neighbor acted. They wanted no part of the hand.

Since everyone else folded, I reluctantly pushed the pot to seat 9. I considered speaking up or calling the floor, but then I thought about it and decided that was not a rules hill I wanted to die on.

It is quite clear seat 9 was cheating. He was seeing if the action was going to blindly check around before betting. It was also obvious that everyone else at the table did not care. Most of the other players would have been more frustrated by the delay in the game by me calling the floor. So I didn't call the floor.

After I pushed the pot and was cleaning up the board, I said to seat 9 that he has to be careful. If enough people check behind him (even out of turn), he might lose his action and his bet wouldn't count. He doesn't say anything for a few seconds, then halfway through my pitch for the next hand he starts going off on me.

He asks me if I am accusing him of cheating? His voice goes higher and gets louder. I say that I am just telling him that he wasn't protecting his action by watching everyone else check. It was fine this time, but it could come back to bite him in the future in a bigger pot where others were interested. Of course everyone else at the table is trying to figure out what is going on and all conversation stops.

He then asks me again if I am accusing him of cheating? I said that I am not accusing him of anything. I was just letting him know that his actions could be ruled differently in the future.

The whole rest of the down he keeps thowing out the cheater accusation. I really wanted to say, "Yes, you cheated", but I didn't. I kept quiet. He talked about going to my manager. When I finally got tapped out, I went to the area supervisor and explained the hand (just as I have here). I said that the player threatened to go to the shift manager over it so I just wanted to explain before that happened.

I don't think I handled it poorly, in fact I think I handled correctly.

I would like to hear others thoughts on this though.