Didn't notice anything unsafe in first segment, water was not swift there, even though it was high.
Didn't notice any down stream safety in the second section through rapids?
Kids are younger then I would personally feel comfortable taking down the whitewater section, though I know nothing of there swimming ability, previous experience, etc.
Second segment get's a "hmmm." from me, first section, that really looked fine, sounds like miss understanding, and cops just aren't familiar with boating.
Am a fan of kids being introduced to boating at young age if it is kept super safe....
We can't always agree, but we can still be civil to each other.