I think it was Mufti Abu Lubaba Shah Mansoor who interprets this Hadeeth to apply to Saudi National Guard (not Saudi Army) and he uses the words “National Guard”. When you actually read about the differences between Saudi Army and Saudi National Guard, it becomes clear why this Hadeeth could possibly apply to Saudi National Guard
www.globalsecurity.org/military/world/gulf/sang.htm
Saudi Arabia really has two different armies. The Saudi Arabia National Guard (SANG) is not like the US National Guard. It is a tribal force forged out of those tribal elements loyal to the Saud Family. The SANG's mission is to protect the royal family from internal rebellion and the other Saudi Army, should the need arise. It is also a counterbalance within the royal family to Sudairi control over the regular armed forces.
worldview.stratfor.com/article/saudi-arabia-new-national-...
The Saudi Arabian National Guard, also known as the White Army, has been a critical pillar of the Saudi state dating back to the kingdom's founding. For over fifty years, the National Guard has adapted to the region's changing political and military landscapes and helped the House of Saud maintain a leading role on the Arabian Peninsula. Today, the Saudi Arabian National Guard is once again at a juncture, because Saudi Arabia's role in the Middle East and North Africa is changing rapidly.