My guess is that you can go much further than the experts predict.
Some cleverness and hacking may be required....
To prevent signal degradation, a solid powerplane has to be close by. Wrap an aluminium foil shielding around the cable and ground it well at one or both sides (I'm not yet sure what will work best: testing required).
To prevent power-degradation, place a capacitor on the power for the camera near the camera. Consider a thicker cable than the one in the flatcable.
I'm guessing a meter will be possible of you consider these tricks. Maybe even 5 or 10m!
A showstopper would be if the drivers at one end are so weak that any signal "sag" will prevent the other side from detecting the signal correctly. You will have an attenuation in the signals. But usually a small attenuation is acceptable, as long as the waveforms are preserved. That's what the aluminium foil shielding is for. It will make the signal cables into transmission lines which just attenuate the signals, but not distort them.
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