[iPLEOMAX]

You should add another parameter "adminid" to your callback.

Like CheckHealthHack(playerid, adminid);
after that, Use SendClientMessage(adminid,......

You are checking "playerid".. if you are sending message to playerid, he will see the message.
I hope you understand what i mean.

pawn Код:

public Explosion(playerid, adminid){
    if(checkinv == 1)
    {
        new Float:health;
        GetPlayerHealth(playerid,health);
        if(health == 100)
        {
            SendClientMessage(adminid,COLOR_YELLOW,"Invulnerability check result : [POSITIVE]");
            checkinv = 0;
        }
        else if(health != 100)
        {
            SendClientMessage(adminid,COLOR_YELLOW,"Invulnerability check result : [NEGATIVE]");
            checkinv = 0;
        }
    }
    return 1;
}

//Example: Admin ID 2 used /check on ID 54.
//Then: 
Explosion(54, 2);