After putting the matter in the hands of a Senior Editor of Wikipedia, he has now reviewed the Wikipedia template of the Brecon and Merthyr Railway by adding five stations to it that were previously not shown on the line running downwards from Rhymney & Pontiottyn towards Bargoed. However, he has made no changes whatsoever to the stations south of Bargoed on that template.
As regards the added five stations north of Bargoed on the B&M line to Rhymney & Pontiottin, no problem. What still needs clarifying is the position regarding Aberbargoed station. The revised Wikipedia B&M map needs further amendment. It shows "Bargoed" with a linking line round it encompassing a station or platform on the B&M Rhymney branch. At that point in the valley the B&M Rhymney branch was on the other side of the river. What existed was a completely separate station about 1/4 mile further north, on the other side of the river and on the north side of Bedwelty Street. It is labelled "Aberbargoed" on the OS map - and this is the one referred to in the Wikipedia entry for "Aberbargoed" - the geolocation reference given exactly corresponds, as do the opening and closure dates given with those you quoted in post #67829. I suppose it's possible there was yet another station south of Bargoed in the vicinity of Bargoed South Junction, but I can find no map evidence for it and it would have been in the middle of the Bargoed Colliery. Interestingly the Aberbargoed station I refer to above had two locations about 300yd apart - in the OS map for 1901 it is at or just south of the Bedwelty Street bridge and looks more like a halt. By 1920 it was a full-blown station well to the north of the road bridge, with two platforms and a footbridge. The station access road is still in existence. NB this is not a confusion with either of the Cwmsyfiog halts - they are visible on the maps close together (although existing at different times) about a mile further north.
As a further piece of evidence, the GWR 1949 timetable shows Aberbargoed as a calling point for trains taking the B&M Rhymney branch, but not for trains taking the main line towards Dowlais, which call at Bargoed.