1) It doesn't show how much stored energy/reduced damage he has.
2) I've taken over 20k damage and when his cd expired, it dealt zero damage.
3) When I matched his fortified cd, it doesn't release any stored energy.
Bolt of Balthakk
4) If you read the text from his ability, it says When the Wand of Watoomb tile expires, Wong drains 3 AP in his team's strongest color, and gains 1 red and 1 purple ap.
However, when you read the countdown text for BoB, it says this instead:
When this goes off, steal 3 aps in the enemy's strongest color, and gains 1 red and 1 purple ap.
5) related to BoB, enemy team's strongest colour was red, but it was draining the target's second strongest colour. They had aps in all 6 colours before the cd went off.
Additionally, it seems like if you fire his Wand of Watoomb to place a countdown tile, then use his purple power to send him away, his countdown doesn't count on subsequent turns. This is something I expected. However, upon returning from Away, the countdown immediately resolves so it might be ticking down secretly?
His coming back from Away activates his spell. Once it gets activated, his cd disappears. It also happens when you fire his yellow while there's another WoW tile. The older cd disappears and another new one will reappear randomly.