Actually, I spent all last night trying everything imaginable and finally I got it figured out. Somehow, the spring that tensions the filament to the extruder gear settled in or got soft at the same time I switched over to the carriage I made to house the Precision Piezo. This was causing the extruder gear to slip on the filament when it needed to feed quicker, but was still fine at slower speeds.
I chased my tail a little bit so I had to bring all the other settings back to normal once the tension was fixed, but now everything is working great.
Thanks for everyone's help, and sorry for wasting your time 🙂 On the plus side, I learned quite a bit by going through everything to try and figure it out.