You pronounce "fête" as "féte" (basically, equivalent to the English "faith" without the "h" sound at the end)?
To my hear these two sound very different.
Not GP but I want to note that the pronounciation of "faith" would never occur in metropolitan French, as it features a diphthong. And in Quebec fête has a diphthong but féte would not have one I think (please correct me if I am wrong), and it is not the one in faith anyway.
No, they don’t.
Some accents use é when standard academic French would use something else. For example, in "j’ai été fêter ça", the 5 sounds "ai", "é", "é", "ê", and "er" could sound pretty much the same. But AFAICT there is no local accent in which both the "ê" in "fête" and "fenêtre" sound like "é". Certainly nothing mainstream.