The Vector 4 and 4-S did receive MS-DOS 2.0 support at some point. I have a working Vector 4 with MS-DOS, and this floppy[1] looks to be for the 4-S. Although larger changes would have been needed to become more "IBM compatible" (of which 4-S was a step).
> They rejected her plan to develop a new machine that would focus on networking and telecommunications, which she saw as the future of computing.
Vector was one of the first shipping a product using twisted-pair networking[2]. It seems that didn't make much of a splash; very little information is available. It was a S-100 board, which maybe limited market appeal by that time.
1. https://www.betaarchive.com/forum/viewtopic.php?t=29115 2. https://groups.google.com/g/s100computers/c/Q8BUj8xHp5E/ (my post)