The two-minute scorecard is a good way to open this. Most small business owners will answer "not sure" to at least three of those five questions, and "not sure" is the honest answer when the AWS account was set up by a contractor who has since left.
Point 2 is the one I see most often in handovers. The key belongs to a deployment script or a person who is gone, it still works, and nobody can say what would break if it were deleted. A credential report plus a short owner column for every key fixes most of that.
I would add one item for teams that buy infrastructure work as projects: write these five checks into the definition of done for any cloud engagement. Root MFA on, no root keys, no SSH or database ports open to the internet, account-wide S3 block, CloudTrail and GuardDuty in every region. Security then becomes part of what was delivered rather than a later audit. How often do you find GuardDuty enabled in only one region?