Fenwick would be FEN-ick.
I'm currently rotating a story in my head about English characters with varying levels of poshness whose surnames are Satterthwaite, Worthington, Forsythe, Tallis, and Hayward.
masculine list:
https://www.behindthename.com/pnl/191050/124079feminine list:
https://www.behindthename.com/pnl/191050/124080