Originally posted by psycho gundamThere is nothing to support this.
bingodeath backdoor'd the cancerverse using thanos as a vessel (which may be the reason he was rejected again, death may have wanted to exact revenge on the killers of her counterpart). therefor thanos could permanently kill in the cancerverse due to the embodiment of death keeping the souls once the character was deceased as apposed to them just hanging around or whatever.
and as far as i can tell, 616 beings > universe X 90% of the time