If SYM and Kymco have ever had any affiliation, there's not a trace of official evidence on the Intarwebs about it, is all I can say with any authority.
IIRC, SYM and Honda were affiliated in the past (and SYM built a great many of the best-selling bikes ever -- the Honda Cub and Super Cub), and went through a very messy "divorce," with bad feelings that continue to this day.
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