Making pink bananas using the approach you mentioned is not possible. A quick explanation:
The fruit-bananas texture will be colored by the game itself, using color multiplication (just like hitcricles in std).
That could work as follows (I don't know the exact algorithm osu! is using, but this should be the most common and behave analogical):
displayed color = texture color * banana color
For the classical RGB color model, this translates into:
displayed color[red] = (texture color[red] * banana color[red]) / 255
displayed color[green] = (texture color[green] * banana color[green]) / 255
displayed color[blue] = (texture color[blue] * banana color[blue]) / 255
Now I'll do that for your files, assuming the average osu! banana color (250, 230, 20) and the color of your texture (240, 115, 190):
displayed color[red] = (240 * 250) / 255 = ~235
displayed color[green] = (230 * 115) / 255 = ~104
displayed color[blue] = (20 * 190) / 255 = ~15
So the result is the color (235, 104, 15) - which is pretty much orange.
=> Because of the blue color component of the osu! banana color, you will not be able to get a pink banana. THIS WAY
However, the overlay will not be colored - you can simply swap fruit-bananas and fruit-bananas-overlay to get the look you desired.