Lonewolf
Can't answer I'm afraid, but I do remember when I asked (many many years ago) being told Boeing flatly refused to act as a sub-contractor to ANYONE on an MoD contract, and MoD (or more likely Government) permitted this. So it isn't necessarily a reflection of what MoD think, or thought, of the company.
Having said that, the context of the IFS comment was Chinook (lack of) airworthiness, and had roots in the cause of the ZA721 crash and the appalling lack of Quality Control and technical know how at Boeing on the device that had been improperly manufactured and assembled; and whose failure was widely accepted as the cause. (I've seen the photos that remain unreleased; they're pretty damning). This was raised in evidence at the ZD576 (MoK) Fatal Accident Inquiry by an RAF officer. That MoD/Government took no action speaks volumes about who has primacy here. Later, similar evidence about Chinook Mk2s was given during the campaign to clear the pilots, and again Ministers took no action.
MoD's Design Approved Organisation Scheme, a complementary process to that which appoints DA/DCs, permits one to take account of such historical failures and refusal or inability to fix them, so you never know, MoD may have finally flexed muscle. But I doubt it!