I have a 2006 Honda Odyssey with 119000 miles. Had a local shop do timing belt and water pump etc. back in July. Serpentine Belt Tensioner pulley just failed (bearing popped out) Belt shredded but did not break right away. Made belt jump as piece of belt wound behind crank pulley. Shop is telling me valves are trashed and not sure what else is recommending a new motor for $3800. Is this something that should have been prevented by work done in July or am I just unlucky as the shop owner seems to suggest?