NVRAM chip dead, failing tests even with 3.6V LiPo bat hanging on it.
What was multimeter repair quickly become scope repair. Not expected detour, tbh.
I guess I'd better go sleep, unless something else died more. (4am here)
Good news - no smoke from DMM. Since I'll be ordering new NVRAM for pesky scope, I'll order optical receiver/transmitters too, but will need more testing.