[Telchar]

From Moria in a south / southwest direction 215 miles, then I look for a river. The closest I can find is Isen close to its scource. I travel down stream untill the Isen is joined by the River Adorn. From there I travel north....

This where trouble comes. According to different maps the place where the Isen is joined by R. Adorn is off balance.
On one map has the point so far eastward that a northward line reaches the River Glanduin that passes uninhabited Ost-en-Edhil and has is scource close to Moria, which has almost always been populated - so thats one possible answer.
On other maps the point is so far westward that a northward line reaches the River Gwatlhó. The scource of Gwatlhó is where the River Bruinen met the River Mitheithel. I cant find any populated dwellings close by...
The third quess is that some see the Gwathló and the Mitheithel as one river - the scource of the Mitheithel is in the Misty Mountains close to the Ettenmoors - I guess the closest populated dwelling is the Eagles Eyries - that my last guess ...