Unless something dramatic has changed in the code, the N1Kv does not support CoA.
You can use the CLI(SSH) instead. That is a link to ISE 2.1 documentation, but the steps are identical in 2.3.
If you simply need the N1Kv to be aware of changes yo...
I can confirm this solution.
I was using a CSR1000v 3.13.00 on ESXi 5.5U3. Ping from VM to VM (or CSR to CSR) would not work. CDP did not work.
Oddly, 3.13.00 works perfectly fine on ESXI 6.0U3.
I tried both CSR1000v 3.16 and 3.17 on ESXi 5.5...