This sounds like an easy way to reduce the cost of a cleanup but it is not so easy.
If it is a biohazard, it should be handled by professionals. Biohazard should not go in regular trash.
If it is just regular trash, it should still be handled by professionals.
Your helpers will not know what the dump allows and what items are prohibited. Even if they do know, will they pay attention to that? We take on the risk by transporting pre-filled bags.
Most likely, the trash bags you use are not professional grade so they are prone to ripping creating a mess either getting to the truck or in the truck.
Your helpers probably do not have a good feel for what is 50 pounds. We try to keep bags at 50 pounds to avoid injuries for our team members.