Melee weapon damage does not trigger combat blocking.

I encountered the same problem, melee weapon damage to a player or NPC is ignored. Looking in the source code it is clear why:

When OnPlayerAttack(BasePlayer attacker, HitInfo hitInfo) is called for melee weapons, hitInfo.damageTypes.Total() gives zero. There is a OnMeleeAttack(BasePlayer attacker, HitInfo hitInfo) hook, but with the same problem, because melee weapon damage is calculated later in the queue. You must use OnEntityTakeDamage (BaseCombatEntity entity, HitInfo hitInfo) for melee weapons, even against players and NPCs.

But NoEscape uses  OnEntityTakeDamage only for structural/RAID damage and unsubscribes the hook if this damage is disabled.