<modsnip: quoted post was removed> You are right that no-one would have been interested in CB but only insofar as the tracking of investigators of MM's case which ultimately indicated leads worth following either to eliminate or to follow through.
In 2016 as far as SY was concerned there was ultimately only one lead remaining to be followed before shutdown. The fact that the continuation of SY's investigation continues suggests it was a productive one which may have been shared with the BKA.
Snip
The Scotland Yard boss, Sir
Bernard Hogan-Howe, said investigators were following one remaining line of inquiry and unless any new evidence emerged, that would spell the end of the British investigation.
Speaking on LBC radio, Hogan-Howe said: “There’s been a lot of investigation time spent on this terrible case.
“It’s needed us to carry out an investigation together with the Portuguese and other countries have been involved. There is a line of inquiry that remains to be concluded and it’s expected that in the coming months that will happen.”
He added: “There is a line of inquiry that everybody agrees is worthwhile pursuing.”
“First of all, the line of inquiry that is being pursued, that obviously is important and it is important that is resolved, and I think it will be. If something new comes forward we will investigate it, but that line of inquiry probably at the moment is the conclusion of this inquiry.”
Sir Bernard Hogan-Howe says police are pursuing one line of inquiry but will wind up case if no new evidence emerges
www.theguardian.com
The fact remains that international law enforcement have cooperated with Scotland Yard's Operation Grange since 2013 and in that time CB is the only suspect in crimes against MM.