EuroATC
AFTNs don't crash per se. They have primary, secondary and tertiary routings. For a flight plan from say Bahrain to Karachi all stations on the route would get their copies by the primary link. Should this link fail they would get a copy by the secondary link etc.
If as you say that in this case UAE was not receiving flight plans then the cause would have to lie with Bahrain as they would have knowledge that the primary link was malfunctioning and therefore should initiate the switch to the secondary link.
Most stations have will automatic switching but perhaps in Bahrain they have a manual process.