First
The fuel was not loaded into the engine. It was loaded into the fuel tank.
Second
You can make the solution more gasoline than diesel by adding more gasoline
Third
After you believe the unpure gasoline is all spent, have the spark plugs replaced
Fourth
There shouldn't be a major damage from the accidental wrong fuel as you have stated there was no JND - just noticeable difference
Fifth
If it bothers you, drain the contaminated fuel by running the fuel pump direct to power and collect the fuel at the fuel filter fitting or the most convenient location into a suitable container.