Turns out the following topic, "Discussion for solved and if your having problems" (viewtopic.php?f=56&t=20202
) Is also about Error C1-2858-3. It would have helped if the topic had the error in the title and if the search function was working when I tried using it. Anyways this topic tells us how to fix a broken TN-C menu issue: Install Ymenu and remove whatever ISO/Homebrew was causing your problem.
To install Ymenu is easy, just go here, "[Update] pyMenu 0.3.1 for VHBL, CEF and PRO" (viewtopic.php?f=52&t=21942
) And pick the version you need (TN-C or ARK) and then dump the files inside into your exploit save folder, then transfer over to the vita and run the exploit. The new menu should show up, from which case you can then use psfiler to remove the cancerous file that caused the error.