This section may need a little explaining, about the Intelligence and Security Committee needing to form before the report, completed in the last parliament, can be published:
But No 10 needs the Conservative nominees to the nine-strong committee to agree to support Grayling because the opposition minority want to vote for somebody else. In law the appointment of the chair is a matter for the committee. As a result the long-awaited document is still yet to be released, prompting complaints in Westminster and accusations from Labour, the SNP and the Liberal Democrats of an attempted cover-up.
Grayling was transport secretary, and a running joke for his incompetence. There has been no cabinet minister in recent years who was so bad at his job. As Wikipedia says:
Boris Johnson has reportedly planned to appoint Grayling to the Chair of the Intelligence and Security Committee. Although the Prime Minister appoints the Committee's members in consultation with the Leader of the Opposition, he has no power to appoint its chair as, by law, the chair is elected by the members from their own ranks. Shadow Defence Secretary, Nia Griffith (Labour Party), said appointing Grayling would "make a mockery" of the committee. Acting Liberal Democrat leader, Ed Davey, claimed the appointment of Grayling would be a "power grab" by Johnson and Dominic Cummings designed to avoid accountibility. Some Conservative MPs have also criticised the possible appointment.
https://en.wikipedia.org/wiki/Chris_Grayling#Chair_of_the_Intelligence_and_Security_Committee
It looks like an attempt to stop the committee from forming - try to get such an unsuitable person to lead the committee that any reasonable MP can't agree to it, so it ends in deadlock. And the report never comes out.