Hi, welcome to the forum.
The Arduino uses 500Hz for pwm output. That should be good for leds.
What do you mean with "ripple" ? You mean small timing differences in the pwm signal ? But that is impossible to see for a led.
The Adafruit board is a nice board ofcourse:
But it does not have 10MHz pwm, it could be 44kHz or 625kHz, I don't understand the datasheet very well.
I can't find the maximum frequency for the pwm signal to the MDL24, but I assume it is a few kHz.
Why do you want to control leds with such a high frequency pwm ?
What is your problem with jitter when you can not see it ?
Did you perhaps connect such a led to the Arduino with usb power and the light was not stable ?