Windshield leaking
I'm not surprised the don't warranty it.
It's something they probably don't have experience doing.
And it can be tricky not to mention reproduction rubber my be inexact.
Normally something like 3M 8509 non-setting is used in addition to the rubber.
Did they do this?
And like the previous poster, it MAY not be the windshield.
But if it wasn't leaking before......
I've used Locktite PL S30 but you won't get the rubber back out.