how to check the scores of multiple entities

not quite sure if its possible, ive been working on a hitbox system for a custom entity and this is what i was using execute unless score @e[tag=hitbox,limit=1,sort=nearest] mob.id = @s mob.id as @s[tag=!death.animation.applied] run function sinoan:mobs/animations/death_animations/list, which works but if 2 entities end up colliding both will initiate the death sequence. what im looking for is something that would work like this execute unless score @e[tag=hitbox] mob.id = @s mob.id as @s[tag=!death.animation.applied] run function sinoan:mobs/animations/death_animations/list which sadly isnt allowed by the game (also the @s is refering to @e[tag=need_hitbox])