John Dean now meets with Earl Silbert, the Watergate prosecutor who had been totally duped by the White House counsel for all these months. Apparently the first meeting isn't as productive as it could be; Dean has so much to tell that it's hard for them all to get it organized.
Meanwhile, during that meeting, Dean is called from Air Force One telling him to be in Ehrlichman's office later in the afternoon. In that meeting, with Ehrlichman and Haldeman, Dean doesn't even admit to the first Silbert meeting, instead implying that it was still to come, and of course Dean is still not letting on what he's actually up to.
The key here was Dean's demand, which Silbert honored, to not tell anyone in the Justice Department what was going on. And that continues on into the new week, with Dean (contrary to his reassuring words to the White House that the prosecutors aren't even interested in anything after the break-in) actually fully detailing the cover-up.