Re: SNMPv3 and USART
There shouldn't be any interference between the TCP/IP stack and the UART. The TCP/IP stack can only use the system console over UART if directed but just sends messages to it. So adding SNMP to your application or not, shouldn't have any effect on the UART functionality.
How exactly do you try to use the UART on the PIC32MZ: the UART driver, the SYS_CONSOLE over UART, UART plibs, direct register access, etc? Please give some details.
If you use one of the provided Harmony services that include the UART, then make sure that in the updated project that added SNMP the corresponding service is still selected.