Folding KKxx on the River: Too Tight or the Right Play?

Sure, let's break this down and provide some advice on how you might have played the hand differently:

1. Preflop Action
Your raise to $0.63 from UTG+1 with KdKhQh2d is solid. It's a strong starting hand in PLO.

After the CO calls and the BTN 3-bets to $2.87, calling the 3-bet is reasonable given your position and hand strength. However, a re-raise could be considered to isolate the BTN and take control of the hand.

2. Flop: T♣ J♣ 9♦
The flop brings an open-ended straight draw for you (KQ), but it also completes several possible straights and flush draws.

When UTG+1 bets $6.72 and the BTN folds, you have to decide between calling and raising. Given the draw-heavy nature of the board, raising to protect your hand and build the pot could be a good move. However, calling with the plan to re-evaluate on the turn is also a defensible play.

3. Turn: Q♣
The turn gives you a straight (KQJT9), but it also completes the flush draw. When UTG+1 checks, this is a good spot to bet for value and protect your hand against a possible flush draw.

Checking back here, as you did, shows caution but might miss out on value and protection against draws. A bet could force your opponent to fold weaker hands and draws, or charge them to see the river.

4. River: 2♦
The river is a blank, and UTG+1 checks again. This is a good spot to bet for value with your straight, as you did with a bet of $5.25 into $22.40.

Given the board texture and your hand, a slightly larger bet might extract more value from hands that could call you, like two pairs or sets that missed their draws.

Addressing Your Questions:
Should you have capped the flop?

Raising on the flop could have been a strong play to protect your hand and build the pot. The flop was very draw-heavy, and a raise could have forced opponents to pay to continue with their draws.

Check-back on the turn due to fear of a check-raise (CR)?

While caution is understandable, betting for value and protection is often better. If you get check-raised, you can re-evaluate based on the opponent's action and your read on their range.

Folding on the river thinking you had a club in your hand?

Ensuring accurate hand reading is crucial. Given that you didn't have a club, betting for value was the right move. Your decision to bet $5.25 into $22.40 on the river seems cautious, but it's better than not betting at all.

Summary:
Preflop play was solid; consider the occasional re-raise.

On the flop, consider raising to protect against draws.

The turn is a key spot to bet for value and protection.

On the river, you played it well by betting for value.

Every hand in PLO is complex and situational, so don't be too hard on yourself. Keep analyzing and learning!

Hope this helps! How do you feel about these suggestions?

(I'm really hoping a sleuth can piece together what's going on itt)

(please disregard the above advice, it comes from a source that's never played a hand of poker. The main benefit of a river bet here is to try to get the same hand off a chop, but given you've got 2 kings in your hand, and people don't like betting without flush draws as much as they like betting with them, I'd just check back and take the showdown unless you know they're payoff wizards otr)