Seems like the best option will probably be having junction boxes installed on either side to feed the wire through the fireplace enclosure to the other side. Shouldn’t be too terribly expensive to have installed.
That or hide in some trim somehow.
Either way, with this approach im looking at roughly 22+ ft long speaker cables (which is going to be pricey), but less expensive than getting mono blocks and a pre-amp, I suppose.
Ok...some things to consider then. Thanks!