Sorry to hear you're having the issues you are.
The program you mention is indeed very hard to uninstall in fact a while back it was badly installed on many computers.
Dell DID have an uninstall for it however and I can't recall.
I do know we had about 2 pages of torture to go through to get rid of the damn thing only to re-install it correctly because it was done that badly.
"Decrapifier" and others like that will fail becasue it isn't bloatware it is indeed the fingerprint portion of the hardware and that's part of the problem, the software is if I recall right activated by the drivers for it.
Here is a link I found that looks a lot like the nightmare we use to go through.
If some steps are not possible go to the next as if you had done it (that's what we had done) and indeed you will notice the steps include one to go into the BIOS.