not a lawfag, but here is some "evidence" to why the distancing between powell and trump's legal team occurred.

Two powerful arguments counsel against intragovernmental litigation. First, the United States is a single entity, yet article II's case-or-controversy requirement forbids one person from being both plaintiff and defendant. Second, judicial resolution of disputes between, agencies may trench on the President's authority, if not obligation, to resolve such disputes as Chief Executive. This separation of powers concern is underlined by the Framers' adoption of a unitary executive, with a single, accountable head-a structure that seems inconsistent with al- lowing agencies to turn to courts to settle their disputes. These arguments are linked. First, the more unified and hierarchical the executive branch appears under article II, the less likely an article IH case or controversy can exist within it. Second, lodg- ing the executive power in the President could be "a textual

commitment" of decisionmaking authority to a branch other than the judiciary.

The shortest answer to this problem is a functional one: if an intragovernmental dispute has actually reached the courts, that very fact indicates that there is concrete adversity sufficient to satisfy article III and that the President is not in fact in control and capable of resolving the dispute, thus belying the unitary executive notion. As a statement of the practical realities of intragovernmental litigation, this is a compelling argument for justiciability. It is, however, a practical rather than a theoretical or systemic response. If parts of the government are not supposed to square off in court, then courts should not endorse and par- ticipate in the derailment of the constitutionally appropriate functioning of the government. Although the very existence of the litigation is revealing, intragovernmental suits cannot be self- justifying.

What I gather here is that POTUS relinquishes his unitary power to resolve intra-governmental disputes simply by allowing it to go to the courts(where a case of CIA election tampering should be decided). Distancing Powell from Trump's legal defense will force the CIA to stand alone in their defense, thusly removing any case-or-controversy protection. My take anyway.

from - United States v. United States: When Can the Federal Government Sue Itself? https://scholarship.law.wm.edu/cgi/viewcontent.cgi?article=1941&context=wmlr