What happened to Charlemagne's body in the year 1000 A.D.?

https://en.wikipedia.org/wiki/Charlemagne

He was buried on the day of his death, in Aachen Cathedral, although the cold weather and the nature of his illness made such a hurried burial unnecessary. The earliest surviving planctus, the Planctus de obitu Karoli, was composed by a monk of Bobbio, which he had patronised. A later story, told by Otho of Lomello, Count of the Palace at Aachen in the time of Otto III, would claim that he and Emperor Otto had discovered Charlemagne's tomb: the emperor, they claimed, was seated upon a throne, wearing a crown and holding a sceptre, his flesh almost entirely incorrupt. In 1165, Frederick I re-opened the tomb again, and placed the emperor in a sarcophagus beneath the floor of the cathedral. In 1215 Frederick II would re-inter him in a casket made of gold and silver.

Aachen is a city in Germany.

Charlemagne was buried with the crown of Hungary.

The Hungarians wanted it back:

In the year 1000 A.D., upon the insistence of Pope Sylvester II, the German Emperor Otto III was ordered to open Charlemagne's tomb and recover the crown. The Pope promised it to the Polish king Boleslo. The Hungarians must have known something about this crown, probably demanding that it be returned to them. So, Pope Sylvester in his dream received a message from God to give this Holy Crown to the Hungarian King for his services to the Catholic Church and for his good deeds to God. Hungary was a powerful country at this time - and if the Hungarians declared that the crown belonged to them - then it was their crown. On Christmas day in 1000 A.D., Saint István (Stephen) was crowned with the same crown that Charlemagne had been crowned with two hundred years earlier.

http://www.chicagohungarians.com/radics/Origin2f.htm

Charlemagnes's body was exhumed by Otto III, in attempt to stop 'the end of the world'.

"1000 goes down as one of the most pronounced states of hysteria over the return of Christ. All members of society seemed affected by the prediction that Jesus was coming back on Jan 1, 1000 AD. Otto III even exhumes Charlemagne's body to try to "delay" the end of the world. Supposedly, at midnight mass on December 31, 999 AD, the Vatican's clock stopped running JUST BEFORE midnight."

http://www.icon.co.za/~cschutte/Medieval_Society_HTML_Final.htm#Charlemagne

I'm not quite so sure that the hysteria was so strong or widespread. The majority of people in Europe would have not even known it was the year 1000, and outside Europe it wasn't 1000 anyway. Why not? The majority were peasants. Illiterate and uneducated (the two don't always go together...), they'd know the day of the week because every seventh day they were expected to be in church to listen to a priest going on incomprehensibly in Latin. (The Latin would sometimes be incomprehensible to a real speaker of the language - really educated men didn't work at the peasant level.)

"What did people living during or near that millennium change think of what we now call "an awesome event"? They never gave it a real thought, at least Lambertus did not consider it to be an awesome event worth reporting about."
http://www.icon.co.za/~cschutte/Medieval_Society_HTML_Final.htm#Charlemagne

I'm also slightly puzzled by the Vatican clock stopping 'just before midnight'. Clocks then weren't powered by clockwork, but were timed candles, sundials (which stop at dark) or water clocks. Candles can blow out (common in draughty places) and water clocks can run out of water (again, probably not uncommon). A candle can indicate 'just before'. Most water clocks indicated the set hours audibly and could not indicate a 'just before'. It was the hour itself that was important for the church services, not five to or whatever. A drip clock can indicate 'just before', but these are notably inaccurate and the Vatican could afford something far more high tech.
https://en.wikipedia.org/wiki/Clock

The other thing that's puzzling me is the corpse being not corrupted, but being smelly. The general state of the population of most classes was fairly unwashed, so any lingering normal body odour would not have been commented on (or even noticed over that of those present). A smelly corpse is decomposing. If efficient embalming had taken place, there should have been no smell. "He was buried on the day of his death, in Aachen Cathedral, although the cold weather and the nature of his illness made such a hurried burial unnecessary." " A later story, told by Otho of Lomello, Count of the Palace at Aachen in the time of Otto III, would claim that he and Emperor Otto had discovered Charlemagne's tomb: the emperor, they claimed, was seated upon a throne, wearing a crown and holding a sceptre, his flesh almost entirely incorrupt. In 1165, Frederick I re-opened the tomb again, and placed the emperor in a sarcophagus beneath the floor of the cathedral. In 1215 Frederick II would re-inter him in a casket made of gold and silver."
https://en.wikipedia.org/wiki/Charlemagne