Divers in SOS: aides probing subject of inquiry – this? (7,7)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

A clue-as-definition: an anagram (‘divers’) of IN SOS AIDES in or ‘probing’ CASE (subject of inquiry) – CAISSON DISEASE is decompression sickness, suffered by divers if they have to surface too quickly, perhaps in SOS situations