I agree with your observations.
What’s puzzling is why the spokesman for the Sheriff’s Dept doesn’t seem to be bothered by the obvious discrepancies.completely
My guess is they are perfectly willing to sit back and let the family basically convict themselves with their own words, knowing that this is a family that thrives on media attention and will keep talking and keep increasing the odds of slipping up like the kid did in the first interview. Colombo would approve of this tactic.