Any thoughts on whether this can be cleaned
Since we cannot see or check for ourselves...unknown.
Everything can be repaired
Comes down to part availability and costs.
The stench from the broiler now is unbearable. I don't actually see any ridiculous residue inside anymore. The stench might be coming from the element itself, because it doesn't happen when I've only got it on bake.
New element time? Burnt insulation? Burnt wires to the broil element? Probably worth having someone come in and check the range out.