[Q] [VK810] Can't Boot into TWRP With Hard Keys topic

I am rooted with TWRP 2.7.0.2 installed. I can boot into TWRP using the Quickboot app, but not using the button combo (power+vol. down, when the logo appears release power, while still holding vol. down push power and vol. up). Does anyone know how to get into TWRP on the Verizon VK810 from a powered off device?