Originally Posted by
lamphs
The other unclear part was that I had good information that if I was stamped into Qatar, I would not need a VOA for Oman. I was stamped into Qatar (left the airport) 24 hours earlier
You needed to have purchased the Qatar-Oman joint visa from the Qatari immigration agent, which AFAIK is supposed to cost QAR 50 (= OMR 5.282).