H4 Stamping for 16 year old kid

My wife and my kids (1st one 16 years and 2nd one 11 years old) are visiting Hyderabad this summer. They got H4 stamping at Hyderabad 3 years back. My wife and my 11 years old kid is eligible for drop box but my 15 years old kid is not eligible for drop box because of reason “Most recent visa was not issued on or after 14th birthday”.

Now my question is - My 16 year old alone should go for an interview and my wife and 11 year old go for drop box? or My wife and both kids should go for the interview together? What would be the best option?

Eldest kid can go for in-person interview while the rest can opt for dropbox.

I am in the same boat. What questions they asked to your 16 yr old kid? Did he go alone or accompanied by the parent?. Please share your experience