The Wikipedia entry goes into greater detail on this title. Very spoilerish... if true.
an alternate Doctor played by David Morissey with the Tenth Doctor acting as his companion.
That element's not true, AFAIK. Morrissey is
Either a fake Doctor as in The One Doctor, or just a Victorian doctor who has adventures, depending on who you believe. His companion, who becomes Ten's companion for the episode, is the black girl seen on location
And TenDoc is just The Doctor as usual.