I am concerned about being denied boarding on a KLM flight to China. I have researched this and am certain I meet the 240 transit without a visa criteria but I am not sure how trained the agents are and what the risk is that I am denied boarding.

I am flying:
SFO-AMS-PEK
After PEK, I have a bunch of trains and flights to get from PEK to SZX.
China Eastern from SZX to TPE
TPE-AMS-SFO

SFO-AMS-PEK and TPE-AMS-SFO are purchased on a single ticket.

My 3rd region is TPE (or AMS) and all of my travel is within approved regions, so I am in compliance with the 240 TWOV.

However, my ticket is booked as a single itinerary which they may view as a return/roundtrip ticket. I am concerned about them denying me boarding and I have seen a horror story of exactly this happening on Reddit. My question is - is there a big risk I will be denied boarding and, if I am, what recourse do I have (I imagine 0).

I fly in about 3.5 weeks and live in another state that would require an agency to get an L-visa (and am extremely uncomfortable shipping off my passport) so I'm unsure how I should proceed at this point.