If most of the VC's concerns are on your list of challenge milestones, then they will be more likely to believe the rest of your pitch as being accurate.
Self-awareness is huge. You should know the reasons why a VC might not want to invest in you, regardless of whether it ever comes out of your mouth or goes on a slide. If a VC is interested but has concerns, they're going to ask these questions, and you'll be better prepared to address them. It's up to you - and situational awareness matters - whether you decide to speak to these points even if you're not asked.
No. Having a list of risks and assumptions you can send folks is good, and shows maturity. But it doesn't belong in the deck, which should be for introducing yourselves and telling your story.