Entombed simply doesn’t cast anymore if you get hit or grav well. There is some lag or interruption going on with the animation so you can’t tell if it did or didn’t cast and if you press a second time then you break it.
It is also vanishing with cooldown blown if you get hit during cast.
Burn Out animation and possibly real location lags so you are doing a super man pose in place then warp forward. It seems we are being hit while in that animation frozen state and melee are easily catching us after the warp. Because the animation is so bad it is hard to tell but I think it is not travelling as far after being hit.
In general melee seems to be interrupting cancelling all casts like there is a stagger on all melee attacks now.