So, my advise; let someone know (controllers if you don’t know anyone else) when you will be arriving at Muscat Airport, there most likely will not be anyone from DGMAN waiting.
Maybe it has changed, but when I arrived a very long time ago, before they had the chance to get used to expats arriving,I was met and whisked through all Immigration stuff by one of the DGCAM Hr guys. I was never sent anywhere without an HR guy there to help.
Can't say what it is like now, but what was written by cripton was certainly not my experience.