Oh dear! It always pains me to hear that someone has used a jet wash on their soft top, unfortunately this is a very common error! It is a shame that you did not spot the marks before you purchased the vehicle.
Jet washers should NEVER be used on a convertible soft top, the concentration of water flow is too powerful, and often damages the top, not only on fabric but also on vinyl.
It sounds like the previous owner of the car may have blown some of the pile of the fabric off with the jet wash and this would have caused the lines to appear as you describe. The Soft Top Reviver will probably accentuate the lines if this is the case.
In the lined areas where there is less fabric for the Reviver to adhere to, less Reviver will be absorbed, so the undamaged areas will soak in more Reviver where there is more fabric for the Reviver to adhere to. This will result in the undamaged areas darkening more than the damaged areas and highlighting the damaged lines rather than hiding them.
Sorry that I can’t be of further help! This is why it is so important to check the soft top thoroughly of any convertible that you are thinking of purchasing!
I hope you found this information helpful!