Doolittle B-25 Russia landing

I don’t know if this has been a subject here before but has there
ever been a serious serach or records located as to the fate of
the B-25B that made a wheels down landing in Russia after the
Doolittle Raid of 1942?

Graig Nelson’s book “The First Heroes” mentions that
several people have devoted much time and effort to
locating it without success.

Thanks
Simon B.