Just watched that and I never heard him say NB couldn’t be in the sea, at all.
Others, highly professional water rescue organisations have said that many people who drown in rivers just miles from the sea will invariably end up there - just as the firefighter did a few years ago after drowning in the river in Lewes. It’s a very common occurrence, apparently.
It’s possible she never even fell in the river for anyone knows, but until she’s Found no one will really know what happened.
What this has established, however, is that PF repeats how he’s been doing this work for 20 years with brilliant results, and how he’d find NIcola within one day - but he hasn’t.