Thief took apart ignition; I tried it and fried something

I come to you guys hat in hand. I’ve read a whole lot of these threads—on ignition, switch, contacts, coil, battery, dizzy, igniter, starter—and I know some of you’ll know this answer without even thinking. I pulled starter, bench tested—great. I tested coil—unsure of m-m, unsure of coil, I read more, and more. Now just feel like I have to go to the well.
I have only street parking for my 110k ’89 lxi, and an old pre-Club bar on the wheel wrapped in heavy chain—and took to pulling battery. So when thieves waltz in with their key, they find there’s a few things they have to beat. In the past they’ve cut the chain, trashed the steering housing, left things hanging—but given up. I clean up the wreckage and car starts fine.
This last time though there was something hanging on its cable by the cylinder and ignition courtesy light/cable that I wasn’t sure had been there before. Tried key, got nothing. Fiddled with the thing, found it had a little spring-loaded tab, thought I’d just hold that down and try key again. Wrong move—check engine light and maybe other dash flickered, I heard electrical frying, and in a second or two released key. But now we’re dead.
So looks like the ‘third’ thing had NOT been hanging there before. I found it fits into one spot on the key cylinder and, weirdly, that the thief had to back one phillips screw out to take the thing off and leave it hanging. And that I shoulda figured that out first and not held that tab down.
All lights, windows, etc are fine; battery was old and weak before and needs replacing, but still takes slow charges.
Either my old unused Sears analog m-m is bad—Rx1k, 100 and 10 adjust to 0ohms, but Rx1 won’t—or I am (I am), or the coil is—per the manual at 24-7, A-D goes clear to zero, A-W goes a little high, and B-D is right at 2200. Maybe the coil, maybe the m-m, maybe me.
I’m hoping maybe I burned the ignition switch contacts, that the orig TEC is old and not perfect but not newly damaged, and that this is Hondas for Dummies for some of you, and a doable fix for me.
Thanks for sharing all this knowledge and expertise, and for anything you can tell me.

Id check the under hood fuses something popped under there I would guess. Be ready to pull the POS terminal of the battery anything weird starts happening.

Thanks a million, Oldblueaccord. But I didn't give myself enough credit, cuz I pulled and inspected every fuse, related or not, under dash and under hood, multiple times before posting here, and the battery's out. I've blown some fuses--buddy hooked up his jumper cables backward--and this was more of a process, fry or burn. But thank you.