Hi,
The king and the queen were laid in single graves. One could identify MA ,with the help of her garter, also one says her head would have lain between her feet how with criminals it was then usual... Moreover, the graves on the Madleine had remained a cemetery unlooted.
The grave of both was without names, but a man knows where this graves are and he look after them.
In 1815 the King and the Queen were exhume and reburied in St. Denis at 21 January 1815.
In the MA Biografie from Antonia Fraser is one qoote, how Marie Therese (the eldest daughter of the king) came to the grave of her parents.
>>When Marie Thérése return after the restoration for the first time to France, accompanied Pauline de Tourzel, in the meantime, Comtesse de Béarn, which daughter Marie Antoinettes to the tombs of her parents. It was seven o'clock in the morning, and the Duchesse d'Angouléme carried insignificant dress as well as a veil about the hat. Both ladies were led by Pierre Louis Desclozeaux, a betagem lawyer who lived with his son-in-law in the Rue d'Anjou 48. He was able to do himself still well to both burials errinnern and had maintained gräber since that time. He reports to the "daughter of the Märtyerkönigs" that the gravediggers with the procedure of the Einsargens of her mother a break had made around her mittagessen to consume and the corpse with the head unguardedly in the grass lie leissen; thus could make the future Madame Tussaud a wax impression of the lifeless face of the queen. To tremble with the Anbick of the tombs beagnn Marie Thérése, fell on the knees and then prayed for the luck of France - a prayer that her parents had spoken very often. The statement of Desclozeaux' was of great importance when both royal Corpses should be exhumed on the 18th of January. The remains kings and the queen were laid out short time in the house in the Rue d Á njou 48, and one spoke prayers, before mans she laid in new coffins which were marked with the royal titles of her owners. On the 21st of January, 1815 a procession took place to the cathedral Sainte-Denis - there was over the 22nd anniversary of the execution Ludwigs XVI.<<
citations: "Marie Antoinette" of lady Antonia Fraser, in 2006
Since 1815 nobody exhumed the graves of the both in my opinion.
And it's also difficult to find genetic Material today to compare with the DNA of the King and the Queen.
The only way is, take the DNA from Marie Therese and compare it with the DNA of Louis XVI and MA but the problem is, that the Government of Slowakia (who Marie Therese have her grave) not allowed to opend it.
And I'm not sure if the French Gouvernment allowed to opend the graves of the King and his family...