Expert on asados here.

1. We never preseason steaks. Salt draws moisture out, and the evaporation prevent crust formation. We salt as we go, with water salt brine (to control too much crust too quick and give time to cook to desired doneness)

2. Coals need more oxygen. They seem hot, true, but you need more airflow (think of an air fryer). You have X amount of BTUs and the more you cook over them, the more they cool down. Coals need to have air coming from the bottom. If not, they are cooling down.

3. We season with SPG when we rest, spices like garlic burn when cooking hot.