Would you say the photo on the Soul Brother release was taken at the same time as, or cropped from the Photos that were used on the Demon release ?, they look pretty similar to these eyes.
Also the Demon release label states clearly that the album was leased from Broadway productions NOT Stax/Truth/Fantasy maybe Fantasy only bought the rights to previously issued Stax product ?
Where/how did Soul Brother get the rights to release it ? if Demon had already done so in the UK ?, this may be a daft question but I'm not an expert on copyright etc.
Just another small point, David Johnson in the sleeve notes shown earlier explicitly states it was never released, I think he would have known.