From the test it appears to be an internet backbone problem. A routing peer owned by Equinix in DC (this one: ae1-br01-eqdc2.as57976.net) is showing very laggy/overloaded response times. Your ping response went from 25ms inside the ISP’s network to 82ms as soon as Equinix joins the party. Your ISP can complain to them, but that’s about it. But don’t blame them for not sharing this, since you’d need a higher level tech to know what they’re looking at.
I see this argument in every connection-trouble thread because the missing knowledge is: Most games/services aren’t hosted in the same city/building. You’re probably not routing through DC and on to Las Vegas for other services you’re connecting to. Kind of like avoiding a street with a lot of traffic. If you take another route, you’re mostly unaffected.
All said, playing from Pennsylvania to Nevada (Las Vegas server) is going to be more laggy than Pennsylvania to Illinois (Chicago server).