Does Toyota platinum warranty cover coolant hoses and hardware?

I bought a used 07 nissan altima from a toyota dealer about a year ago and am now leaking coolant. I took it to the dealer and they said they could not find any leaks and it did not overheat for them. I picked it up and a week later noticed that it was still leaking, and by the lack of coolant in the resevoir, it has been leaking since i picked it up. I removed the front splash guard and saw that the hose clamp for the lower radiator hose is broken on one side, which i told them to check and they obviously didnt. I was wondering if this would be covered under my warranty? In order to get my money back because I was charged diag and tow since they couldnt find any leaks and therefore werent able to fix anything.