In sp compaign skiff always stuck in terrain textures and nothing help. Devs add possibility to reset damn skiff.
This just happened to me. Skiff is stuck at bridge house cannot get back on it to progress. As you say a reset skiff needs to be programmed into the game as my checkpoints just reload the same glitch and the game cannot be completed now.
Luckily the game glitched again and x lit up after throwing rockets at it