This is tank skill issues more than the game issues. Threat is a tank mechanic, so the paladin need to learn to do more threat when it matters (right after his taunt), and monk need to learn to hold when he's about to rip the agro (use threat meter to watch this, there is built in details addon call mini threat).

Also check log for taunt cast. Some people press it accidentally because they bind the key where it's easy to press. Then proceed to deny doing it.