I can't find any clear references to DARPA (or ARPA) being involved in Ada's development. It was a DoD program but, well, the DoD is notoriously large and multi-headed.

(But even if DARPA was involved in Ada: I think it's clear, at this point, that Ada has been a resounding success in a small number of domains without successfully breaking into general-purpose adoption. I don't have a particular value judgment associated with that, but from a strategic perspective it makes a lot of sense for DARPA to focus program analysis research on popular general-purpose languages -- there's just more labor and talent available.)