In startup speak the organizations have the same VC and share many board members.
The actual committees:
https://intelligence.house.gov/ (23 members)
https://www.intelligence.senate.gov/ (14 members)
So that's 37 members of Congress they're accountable to, but not directly. If you read the actual law, it only says the "President" has to inform these committees of what the intelligence agencies are doing, and if they happen to do anything illegal, the President has to tell Congress (but only these 37 members).
Theoretically, the President is not above the law, but as we've seen in recent history, if the President is of the same political party as the majority party of Congress, they're not likely to actually enforce the law.
Practically speaking, all of Congress isn't going to care what all of the Executive Branch is doing all of the time given the limited number of hours in a day, which is why they they have committees, but at least in the case of the CDC, NASA, and IRS, if all 538 members of Congress request information, they have to give it to them. With the NSA, only 37 members of Congress are authorized to even receive information and only through the President.
Not only is the analogy questionable with board members, but it also carries the implication that they are essentially the same sorts of organizations. They are not.
If you really want to carry this analogy out further, you probably need to expand it so one is a traditional startup and the other a charitable non-profit, or something of the sort. Even if you did have the same people in charge (which again, questionably applicable here), the goals, transparency, and measures of success vary so wildly that I'm not sure it means that much.