We’ll never know for sure as the payload is likely lost for good.
Since the balloon was observed shot down and splashing down by eyeballs on the beach into known shallow waters, it’s reasonable to accept that the water was towards 40-50 some feet deep.
If this logic doesn’t work for you…. Research it out yourself. Location is off Myrtle Beach, SC. Adequate coastal and fishing charts for this purpose are available online.
“... said a State Department official, who provided a statement on the condition anonymity to discuss the information...”
At which point, you discard ALL the information from this article since:
a) there is no need to be anonymous
b) there’s probably no way to know things that fast.
c) an article like this, if accurate, should not have even gone out in the first place.