[idw]

Some thoughts, worth what you paid...

You can't share enough information here to get really good advice. If you do this you will need someone whose advice you trust, who understands your weaknesses as well as your strengths. Could be a friend, could be a coach.

As someone else said, if you can make this a win for everyone involved, that's the best and most likely to succeed approach. To do that starts with asking good open ended questions and listening to what those with the power to make this decision want for themselves, especially the CEO, and showing them respect.

People may express confidence in you now when you're not in charge. Inevitably if you do end up in charge you'll end up less popular. If part of what motivates you is what other people think of you, be careful.

Know your plan b, and c.

Good luck to you and everyone involved.