Running discovery on a SNMP v3 OID that is at the end of the MIB except for an empty table causes the discovery rule to fail. The snmp walk for this situation looks like this:
snmpwalk -v 3 -u username -l authPriv -a MD5 -A password1 -X password2 192.168.1.131 VEMS-ALARM-MIB::vemsAlmGrpHotGuardLeafName
VEMS-ALARM-MIB::vemsAlmGrpHotGuardLeafName.1050001 = STRING: "group_001"
VEMS-ALARM-MIB::vemsAlmGrpHotGuardLeafName.1050001 = No more variables left in this MIB View (It is past the end of the MIB tree)