Finding and identifying the body would be impossible at this point. I was more referring to eliminating the confusion over whether or not the blood staining the document to be sent to Robespierre's Section that night (the one where his signature is incomplete) is even his blood. Or whether the gun handed to him by Lebas has ever been fired. If Robespierre did not attempt suicide on Thermidor 9, there is a small chance that it has not.