I have a leak in my lead shower pan and it is only 4 years used. The contractor doesn't want to know about it now!!

My questions are... do you think the contractor should repair it...I paid him close to 300k for the remodel job on my house??

The job will cost about 2200..Shower door removal and reinstall 800/ plumbing 800/ tile work 600.

Secondly,do I go back to lead pan or the new plastic lining???

BTW I did all the tests and I'm sure its the pan. I had a Shower Grouter come in and tell me that i would be wasting my money if he took the job!

any ideas??