How can I validate my implementation of Ansi 9.19?
Bouncy Castle has an ISO 9797/ANSI 9.19 Mac implementation with a test vector.

Botan also has an implementation and test vectors, which cross-verify with Bouncy Castle (at least the 128 bit key ones anyway).

From the looks, official test vectors appear to be scarce (unless you want to pay for a copy of the standard and chance one being in there), and it's less than clear that the BC/Botan vectors are official, so cross testing with existing implementations might be the best you can manage.