It is possible that the instacure will protect the color, however the commercial products that we have seen does not use instacure in their cure formulations either. Here is an example:
One of the reasons we did not use it was that it would be pretty hard to measure the small amount that would be necessary for such a small piece of meat which was half fat anyway. Each one of our pieces weighed less than a pound.
When we sliced the finished product thin the color was really nice and bright:
The product you see on the skewers is Duck prosciutto