Final answer:
The provided text does not contain relevant historical information about the event in Messina regarding Count Tancred and Richard's sister's dowry, hence a factual answer cannot be given.
Step-by-step explanation:
The information provided does not contain historical facts regarding Messina, Count Tancred, or Richard's sister's dowry. It appears the text is from a work of fiction and therefore cannot be used to provide a factual historical answer about the events that took place in Messina when Count Tancred refused to pay Richard's sister's dowry. Without accurate historical context or details specific to the question, I am unable to deliver a precise and correct answer.