One for me, is that it wasn't cold water, according to the article, and Navy Seals are kind of like human aquatic beings themselves since they practice regularly in the water.
Is that one of the issues you find to be weird? I can see one, but two Navy Seals going missing really makes it even more weird indeed.
Yes. Two SEALs drowning is very odd in standard ocean conditions.
I think the story is a lie, or vital information is being left out.
Not really. They are human beings. They have been known to do things like break their backs while hot dogging in Mark Vs. Shit does happen, and when it does, it is usually at the worst possible moment.