I don't know if this was brought up before in another thread but the following video seems to indicate that Bekele may in fact be the world marathon record holder and the Berlin Clock in 2016 malfunctioned or was tampered with. It also indicates that Geoffery Mutia complained about a problem with the Berlin marathon clock in 2012.
https://www.youtube.com/watch?v=sHX64HCI5_s
A post race article about the 2016 Berlin marathon can be found here:
If someone tampered with the clock why would they do this?