I have some good news.
I was planning on uninstalling each Windows (Security) Update one after the other; rebooting; then trying the CE 7 build using VS2008 on each pass. However, after the most recent update was uninstalled and the system restarted there was a new update installed. Since updates are being forced onto the PC beyond my control, I tried the CE build and lo-and-behold it started.
The Win 10 x64 PC is running build 17763.404 - Version 1809.
Removed Windows update: KB4490481 2-May-19. (It’s unknown if just this was the root cause)
Windows update that appears to fix the problem: KB4476976, 3-May-19
Update: Just to be sure I reinstalled KB4490481; Reboot; Run CE Build - PBSpawn error - FAIL
Uninstall KB4490481; Reboot; Run CE Build - SUCCESS.
Conclusion: The error appeared long before KB4490481 was installed (yesterday). So there’s more dynamic to this than meets the eye. Perhaps a combination of the two aforementioned updates that resolves this issue.
I sincerely hope that my efforts help out others. Thank you so much for your help.