If it were me, I’d have issued them all with one of these:
We’ve been using one since 2008, with no problems at all. They’re a favourite for location work, so I’m sure the Beeb have a few dozen lying around. As to the quality, try this - just stuck the Zoom on an empty pew at the front of the First Derry Presbyterian Church and pointed it at the piano:
OK - it was professionally mastered for release, but then so were the studio recordings on the same album - and that would also be the case at the BBC. The point is that the raw recording (only intended to be a document of the première) was of a sufficient standard to be usable.
The current model, the H6, uses interchangeable capsules, so is adaptable to a huge range of recording situations. We’ve just never seen the point in upgrading while the old one still works! (And if you’re really concerned with quality, you can plug in any mics you want - it has phantom power