Sessions refers to Wray by name. Rather than try to state my impression, which might influence yours, read Sessions' letter of march 29, looking for references to people and positions.
I was paying attention to signs of cooperation (or not) or division of oversight between Sessions/Huber and Rosenstein/Mueller sort of thing.
While Sessions does mention some names initially, his latter paragraphs utilize titles as he is sort of outlining the duties. He used the term Inspector General several times before using the words DAG.
Altogether, there was around 7 Inspector General, 3 Attorney General, 2 DAG, and Senior Federal Prosecutor. Given that the term DAG was within those paragraphs, I would not assign very much importance to the term as being indicative of any future action with respect to RR. JMHO