The International Committee for the Red Cross (ICRC) finds uncontroversial the notion that wounded and hors de combat are not the same. They acknowledge that individuals can be “wounded or sick, whether severely or not, but … not (yet) incapacitated by their medical condition.” Wounded combatants can continue to fight, and contemporary adversaries have engaged in tactics such as “playing dead” or other forms of perfidy.

Standing alone, the fact that an enemy is laying still on the ground is insufficient to determine that target has fallen out of the fight. Also, the mere appearance of visible wounds is probably not enough, unless the nature of those wounds makes it clear the person is unable to defend themselves or unable to continue to fight. Clear indicators of hors de combat from wounds include decapitation or an amount of pooling blood that makes it plain and obvious the enemy’s injuries were mortal. If an attacker is not convinced an enemy is out of the fight, that enemy continues to be a lawful target and can be attacked or reengaged.

However, the practice of automatic, indiscriminate attacks on downed enemies to include a technique or standard procedure of firing “security rounds,” “double-taps,” or “death checks,” is unlawful. The possibility of a theoretical threat from general enemies is insufficient—the determining factor is a good faith belief that a specific enemy, though wounded, is not yet out of the fight. Unless a reasonable attacker would be convinced a wounded enemy is out of the fight (or the wounded enemy is clearly, genuinely, and unconditionally surrendering under circumstances when it would be feasible to accept that surrender) the law presumes that the enemy remains a lawful target.

https://lieber.westpoint.edu/down-not-always-out-hors-de-combat-close-fight/

There are videos that show a clear violation, but this is not one of them.