Pasensya na, medyo naco-confuse lang ako. As per your previous reply, ang issue na ito affects wireless LAN. Tapos concern ka na pwede ma-trigger ang vuln via DHCP packets. Well, kung authenticated at associated ang isang wireless LAN in the first place, getting an IP is less of your concern. They can just assign any static IP within your range and they're good to go. Ang katapat nito sa wired LAN, is they are able to physically plug in their ethernet cable sa switch. The mere fact that they are able to authenticate and associate with your Access Point should be your immediate concern.
And they don't need to go anywhere, they just need to go direct to your router interface and trigger the said vuln.
Unusual spike sa traffic? DHCP packets are really, really small and not enough to cause any spike at all.
Pasensya na, gusto ko lang din malinawan dito.