It always difficult talking to powerful people. Based on what you shared, I think you should speak to your boss and the CIO if you're comfortable doing so, and you can get a positive outcome based on interpersonal dynamics. Here's what I suggest:
Approach your boss with a problem and a solution. When you have the opportunity, tell him you need his help with a situation. Explain that you understand his desire to jump right in, and you're happy he has confidence in you to do the work (or important projects). But, when there are roadblocks or functional issues, and you can't deliver for whatever reason, you feel that it impacts your professional relationships with colleagues or executive leadership. Explain that at your level within the company that's a big concern. Say that it affects your credibility with the other people/departments. Then, ask if you can talk it through or figure out a strategy so these situations can be avoided in the future.
From there, suggest solutions. 1. Suggest that you interact more directly with the internal customers to understand their needs and gather pertinent information before committing. Or, 2. Ask if he would be open to you creating a process where requests can be submitted electronically. Executives are often happy to sit at their laptop and answer a few questions if you give them the opportunity. Make it simple. This would allow you to review it with your boss and consider some of the complexities. It would be great if you introduce the new process in a meeting. Alternatively, you can avoid the process by getting an invite to their meeting. group Try to get 10 - 15 minutes to give updates and talk about new requests, and then bolt. What's critical is to appeal to what's important to your boss. You might want to talk about how efficient it is, minimizes rework, helps with resource planning. All of which impact his bottom line. Another benefit of course is that his peers might appreciate it.
Now the other part. If I thought my professional reputation was taking a hit, I would be tempted to casually reach out to the CIO the next time I saw her leaving a meeting, or passing in the building. A quick "Hi, how are you? Do you have a moment? I wanted to let you know...." Keep it light (this is a chance encounter) but apologize that you are unable to deliver, but you are keeping tabs on the situation and sharing updates with your boss. This might give you an opportunity to open a channel of communication. This person might be your best advocate for change. This works only if you think your boss won't get upset (we don't want consequences).
Hopefully, these ideas will help you figure out an approach. Whatever you do, planning is essential. Know your key talking points and have a strong opening statement, so you sound confident and don't stumble all over your words. You want to be in control. Use notes if you need to! Referring to them is much better than forgetting or rambling.
For more advice, read how to approach your boss about a problem at work.
Good Luck! Keep me posted.
Your Office Mom