Well gave it another half dozen tries... sitting in the center helped a lot BUT there were still times when I was totally in the clear and still lost something like three quarters of my health from a single hit. I mean I was standing right next to Graha and he took zero damage. Doubt there's any official way, but I used a ping mod and see I am running around 80ms in game. My recollection is that is the figure I have always in the past gotten... matter of fact I just ran a ping test to 204.2.29.82 and got back 77ms to 92ms for 10 pings averaging around 81ms (data below). I know it's not my usual 20-30ms (just pinged google, got 11ms to 19ms, average around 13ish), but is that 80ms not good enough? MY internet connection is not in any way an issue here, it's on SE.
I very much have seen this issue in other combat content. I make the move at the right time and still take a hit. Sometimes there's no other telegraphing but the target marker on the ground. I move out of the target marker, am on clean ground, and I still take damage. But now I recall someone I knew was with me and they said I did not move out of the targeted area. Maybe I need to video record it...
PING 204.2.29.82 (204.2.29.82): 56 data bytes
64 bytes from 204.2.29.82: icmp_seq=0 ttl=50 time=82.540 ms
64 bytes from 204.2.29.82: icmp_seq=1 ttl=50 time=85.303 ms
64 bytes from 204.2.29.82: icmp_seq=2 ttl=50 time=89.148 ms
64 bytes from 204.2.29.82: icmp_seq=3 ttl=50 time=80.984 ms
64 bytes from 204.2.29.82: icmp_seq=4 ttl=50 time=82.138 ms
64 bytes from 204.2.29.82: icmp_seq=5 ttl=50 time=84.365 ms
64 bytes from 204.2.29.82: icmp_seq=6 ttl=50 time=82.143 ms
64 bytes from 204.2.29.82: icmp_seq=7 ttl=50 time=80.039 ms
64 bytes from 204.2.29.82: icmp_seq=8 ttl=50 time=83.504 ms
64 bytes from 204.2.29.82: icmp_seq=9 ttl=50 time=79.814 ms