The evaluation of mixed reality audio is typically approached under the paradigms of either authenticity or plausibility. While the first refers to the identity of a real and a virtualized sound source, the latter measures the degree of belief in cases where no direct reference is available. We refer to transfer-plausibility as the ability of a virtualized source to stand alongside multiple real sound sources. We present a perceptual experiment where listeners detect and identify a sound source as being virtualized using dynamic non-individualized binaural rendering under varying scene complexity. Scene complexity is controlled by a varying number of loudspeakers. We demonstrate that the presented methodology mitigates ceiling effects, typically encountered in authenticity and plausibility tests.