The front ones don’t seem to be hidden, but yeah - if they’re not meant to be used regularly, people won’t remember them in an emergency. I guess the rear ones are hidden because they probably bypass child-locks.

I don’t know how child-locks work on mechanical door latches. If the vehicle locks when in motion and the child-locks are on I don’t think there are emergency releases on most vehicles? The only ways out would be to get into the front cabin, break the windows, or find the internal boot release.