A combustor of a combustion turbine engine is described. The combustor may include an inner radial wall, which defines a combustion chamber downstream of a primary fuel nozzle, and an outer radial wall, which surrounds the inner radial wall so to form a flow annulus therebetween, and the combustor may include a socket extending from the outer radial wall into the flow annulus. The socket may include: a mouth formed through the outer radial wall; a floor offset a predetermined distance from an outboard surface of the inner radial wall; impingement ports formed through the floor; and an axial nozzle.