The original raster image is fairly good quality, the pixel dimension is not too small and more importantly there is high contrast between the colors:
See both automated vectorization results and manual vector conversion. At a glance both seem acceptable vector drawings:
But a closeup of the auto-trace results shows some of the detail in the faces is gone. A person with elevated attention to detail will not find this vector conversion acceptable.
Closeup of hand-drawn vector conversion. Note the little noses have a better resemblance to the original artwork:
So taking a few more minutes (or paying a few more dollars) to manually redraw this simple vector image may be worthwhile.
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