RSD will not flash TWRP img's.
You will need to be in Fastboot mode in order to flash anything. If you can get there, I would reflash your recovery of choice, then boot immediately into that. Then restore your backup img.
If that fails, then download the image at
Please Login or Register to see this Hidden Content
and flash that with RSD.
Sig by
livinginkaos
Samsung S8+ / Pixel XL 128gb / iPhone 7+ 256gb / iPad Pro 12.9" / Samsung Chromrbook Plus / Pixel C / Nexus 6p 128gb / Nexus 6 / Nexus 6 on Fi / Nexus 9 / Moto 360^2 / Nvidia Shield TV Pro / Nvidia Shield Tablet / HTC EVODesign on FreedomPop / Chromecast / Surface Pro 3 i7 / Samsung Tab Pro 12.2 / Lenovo Win8 Tab / Eee Slate / '13 Nexus 7