2002 Dodge Caravan water pump

Engine Cooling problem
2002 Dodge Caravan 4 cyl Automatic 95000 miles

I have my 2002 Caravan in the shop for a water leake. I'm not surprised that they said it was the water pump. 4 days later after them telling me that the timing belt cover was bad, they say that the timing belt tensioner is bad and that its what caused the water pump to fail. This additional kit to fix the tensioner will run me an additional $300.00 +/- for a total job of $1000.00 +/- I am starting to feel as though I may be getting screwed. Whats your opinion? Is there any relationship between the timing tension pully and the water pump, that could cause the pump to fail/leak?