User blog comment:MegamanZero0002/Second All-Stars Speculation and Potential Ideas/@comment-24152851-20140420084930/@comment-1427230-20140421231049

I think the idea was to make the ratio 7-7 for both S1-3 cast and s4 cast as well as boys and girls. So to do that the last spot had to be filled by a male ROTI competitor. Although why they chose Sam over Brick if that's the case still doesn't make sense then. Only theory I can think of is they wanted Brian Froud on the show and since Harold couldn't return with the vet cast already chosen they went for the next best thing.