The Hosa DOC10 cable does what I need in that it allows a conventional
Insert connection on a mixer to be used as a Direct-Out.

The trouble is that I need 24 of these and I think I can make them
myself at a lot less than $11 apiece for a 6-inch cable.

I'd like some corroboration of my guess of how this thing is probably wired.

The mixer end is TRS with T=Send and R=Return and S=Ground
The other end going into the DAW is an unbalanced TS connection.

So, the T and S shorted on the mixer side, and connected to T on the
other end?...then of course the S on both ends is common. Right?