The OP missed a previous thread on Omnias with M&RIE receivers: ReSound Omnias with M&RIE Receivers
Around this post in the thread referenced above there are some graphics created originally by ReSound to illustrate what types of hearing loss work with M&RIE receivers and either occlusive domes or custom molds. I violate their recommendations with ski-slope loss that’s a tad too steep by their recommendations by wearing very occlusive molds. ReSound Omnias with M&RIE Receivers - #31 by JT337