Not much I can add at present as on the day the mist was often heavy and the site lies in a probably marshy area. The site is visible coming down the road to Kirkhouse and all along the coast from there. To get there would seem to require a time of year when only grass occupies the field about.
I did try to get there going by the drystone wall past the other Kirk Ness mound on the coast, where the bed of yellow flag just where the Kirk Ness Dyke turns probably indicates the old loch shoreline (the Kirkhouse Burnt Mound at ND47169119 stood by the far edge of the same shoreline), but even that pasture soaked me below the knees and seeing no features through my binoculars I gave up the attempt.
Its one-time ascription to a Danish fort does make you think broch, especially as a local farmer found a "Pictish house" over by Manse ( 3' wide, 2 1/2' wide, 11' long and neatly paved. Most likely a souterrain, quickly reburied). But if it was rather on an island then the two site-types that it could be are a crannog (like the ones at Voy) or a causewayed island dun (as Wasdale supposedly is). Might be none of these.
RCAHMS NMRS No. ND49SE 7 at ND47289130. Locals once thought this mound, heavily quarried at various times, to be "an ancient Danish fort". This green roughly circular knoll (about 30m by 2m) was either on the shore of a loch drained long ago or else on an island in that loch. Site-type is not known.