There is really one one lounge open in DOH. the Al mourjan lounge. Which is one of the best bus class lounges in the world. Usually all J passengers on miles get in. I flew R class on QR recently but am EXP/ Emerald on american and they "granted" me access which is not typical.
folks on miles in Bus class always get in. their staff is usually well trained so perhaps a newbie manning the esclator.