Retrieves an entity index from an entity's property.
This function is considered safer and more robust over GetEntDataEnt*, because it performs strict offset checking and typing rules.
int GetEntPropEnt(int entity, PropType type, const char prop, int element)
Element # (starting from 0) if property is an array.
Entity index at the given property. If there is no entity, or the entity is not valid, then -1 is returned.
Invalid entity or offset out of reasonable bounds.