Francis was just chilling in his knight armor, when a man came from the future with a dumbell and dropped it on him, effectively killing him.
I'm, like, gonna kill you
The man became sad, and decided to bury him. While this was happening, he started crying while also working on his gymnastics. Francis was completely covered.
Within a few hours, the section of the Earth that Francis was in froze. It broke off and started to drift into space. He went through a wormhole that caused him to experience time quicker than in Earth.
Francis and his rock/ice drifted back into the wormhole. It had been 3 million years to him, but only 300 years on Earth. The rock boomed into Texas. It cut into the Earth so hard, it went all the way into an aquifer, which was cool enough to keep the ice in a solid form.
Francis wasn't found until 2050, when a company found the aquifer and wanted to use it. They found him and called some paleontologists to take care of the body.