Connect to your computer and open TegraRcmGui, if it says “RCM O.K.” Then inject a payload. If it says “NO RCM DEVICE DETECTED” then it could be one of two things:
1. You fried your Switch
2. It is stuck between RCM and Regular, and can be fixed with a hard reset, or by repeatedly holding the power button until TegraRcmGui says “RCM O.K.”
Edit: And please just buy a RCM Jig, they are so much simpler