My ping isn't that bad (about 150ms currently) but I played at 5-9 fps for the longest time which is even worse. I basically had to remember every encounter by heart and start moving before the aoes showed to avoid them (titan was the worst). Perfectly doable and I rarely ever got clipped but obviously requires a lot more work (also things like your dps naturally suffer in the process).
Some things to be aware of, if there's a multiple ground aoe mechanic that people stack for, don't stack with the rest of the group, they never stack perfectly and any missplaced aoe will basically hit you. You can generally always stack in line with the others, just not on top of them.
We have faith in you. You can do it!