It spawns in a random interval (min 10 minutes, max 70 minutes) at a random spawnpoint. That means it could spawn up to 6 times within an hour, or not at all.
Well around 7 dog meats that are spawn by around 10 people that would be around 60 dog meats and the server will sertanly will not support that why dont you just make it so only 1 or 2 dog meats can be summoned by each person with a time limit included.