That is a round trip, not one way.
Okay, I see what you're saying. And you're right.
The one-way speed of light is unresolvable, because a precise measurement requires a clock at either end and at the level of accuracy that is needed, the two clocks won't give exactly the same reading at two different locations because of the very nature of the universe.
Stephan Hawking I'm not, but I'm not sure "unresolvable" is the same as "unknowable" in the sense of being unable to arrive at a decent working approximation suitable for mundane engineering tasks, like we do with the figure for Pi, which is also unresolvable.
We do in effect "measure" one-way speed of light via satellite, GPS, Webb, Hubble, Perseverance, Lucy, Dart, Voyager, Juno, etc., etc., etc. It's not a measurement suitable for theoretical physics, but a substantial difference in forward and return trip speeds would require a substantial difference between earth clocks and the internal clocks in these devices. In a few of these examples, it would have to be minutes as opposed to fractions of a second.
I guess I can't categorically deny that (Never thought about it before) but if so, it's definitely new to me.