If it was the OEM glass wind screen perhaps but it was an after market STC'd item thus I can see an out for Sikorsky in that regard. That being said, if Sikorsky knew of the problem and did not issue a letter pointing it out to the operators (as they did after the accident) then I can see a problem for them in that regard.
A collateral issue for PHI if examined closely by an attorney for the plaintiffs is the hard nosed...take it or leave management attitude that prevailed/prevails at PHI. Common talk amongst the pilots has long been the quickest way to find yourself looking for a job is to make any kind of noise that challenges the way business is done. No matter what PHI management wants to say about that, it is bound to carry over to the safety program and safety environment within the operation.
Where the dollar is King....safety will always be a Serf.