I thought much of the exptools went into something whos name was like the AT&T Unix Toolkit Library (that Summit maintained). It was subscription oriented (you paid per tool, but had an unlimited license for it). This was how Korn Shell for $2K and a few other things made it out of Bell - I think that eventually, ditroff was moved there instead of being a separate distribution. I've now forgotten many of the details - there was a build/make replacement IIRC that was there also, many of the Jerq tools and games like GBACA and some others were in there. Thinking about it much of the support for Jerq (68000) and Teletype version (BLIT/We32000) may have been in the Toolkit library.