Can a Rogue with Rogue Crawl (Ex), charge while prone and crawling. Assume that there is just clear space and open ground between the rogue and the target. I think it comes down to the line in charge, 'nothing can hinder your movement'. Rogue Crawl lets you move at half speed while prone, so I'm not sure if your movement is officially hindered.
I can't find a definition anywhere for 'hindered' movement, but I found one for 'hampered'. They seem to be used interchangeably, as seen in Soften Earth and Stone, which uses hinder where they could have used hamper.
Looking at movement, they use the word hampered. So our movement, while prone, is officially not hampered, as that would be the result of intervening difficult terrain, obstacles or poor visibility, of which there is none.
If the Rogue is hindered by being prone, would Freedom of Movement allow them to charge while prone, if they had the above feat?
Note: I realize that hamper's definition is 'to hinder', but I'm looking for a RAW explanation of if I can or can not do this.