All those adaptors feels a bit excessive.
I'd forget about the one you've got (since it's meant for a desktop machine), get one of these and combine with this or just use an actual compact flash card instead of SD.

a 44PIN IDE native solution *WOULD* be much cleaner. No argument.

Hope some of this is useful. I've spent a couple of days tinkering with my T1850C - I stripped the bios and AI tells me that these are the disks that function.

1 CP2024 Conner 20/21 MB
2 CP2034 Conner 34 MB
3 JD-E2825P JVC 20/21 MB
4 CP2044 Conner 40/42 MB
5 JD-E2850P JVC 40/42 MB
6 CP2064 Conner 60/64 MB
7 MK1122FC Toshiba 43 MB
8 CP2084 Conner 80/85 MB
9 JD-E2085M JVC 85 MB
10 MK2024FC Toshiba 86 MB
11 CP2124 Conner 120/121 MB
12 MK2124FC Toshiba 120/130 MB
13 AB140 Western Digital ~40 MB
14 AH260 Western Digital 63 MB
15 AH280 Western Digital 85 MB
16 CP2088 Conner 85 MB
17 JD-E2130M JVC ~130 MB

My potential solution here is to use a "SFRM72-DU26 720K USB Floppy Drive Emulator" that converts the floppy drive to a usb drive (fat16). Apparently this is unlikely to work fresh out of the box and will need some tinkering.
From there I will flash my Chatgpt amended bios that skips the hard drive whitelist check.

From that point I plan to install a 500mb CF card (or 2gb formatted to 500mb) and see if I can get it to boot.

If this works I'll be happy to talk anyone through what I'm doing.