When MVT has completed and is unable to repair, you are prompted to contact Technical Support Chat who should be able to resolve the issue for you.
DAT's take time to reach all the world's servers so often you will find that you are 1 behind. That will be rectified in due course. The boot DAT is perhaps misleading in that it appears old, but that is simply the DAT used at first boot prior to the SecurityCenter initializing.
Mine is 6435 so disregard MVT for now. Uninstall it as it never updates itself and has to be downloaded and installed again when needed.