I remember the stuff about The Scotsman - Pratchett had something similar with the Times - but I hadn't heard anything specific about Stouffer until that just there. In fact I hadn't heard of Stouffer until well after the urban legend of Sandman (not Stardust!) was doing the rounds...
... and Gaiman there reckons the rumblings about the Rowling/WB suit against Gaiman/BOM started with Stouffer in 1998, but with Gaiman as the litigant? The early internet really was a different time.
Weirdly Gaiman says there that WB "optioned" Sandman before HP was ever published. It kinda fits - WB was adapting DC stuff at the time already, because they're the same company - but I don't recall anything serious about it until the early-00s. Looking into it, Wiki says there was a script in 1996 (pre-Potter) and another in 1998 (post-Potter), based specifically on Gaiman's Sandman (he doesn't own Sandman, as he says, but as he's repeatedly been involved in scripts for productions based on his Sandman I imagine he has some part of a finger in that pot), then not much until 2007 (the one I recall) and a new Goyer treatment in 2013, and of course it's now coming to Netflix.