How much would it have cost if you flew UA? $199 first class is still cheap. I'm guessing you still saved money?
That said, they should at least let you know there will be no IFE before the flight. They market Red etc as part of their product, which is what their customers expect. You were let down and a voucher for 12.5% of the purchase price doesn't really cut it. I'm a big fan of VX, but I'm disappointed on how they handled this.
If there is (at least) one A319 that is not fitted, does that mean that this occurs on a regular basis? That's not good.