It really depends on country of origin for the individual, afaik Bulgaria or Romania have lower then 15%, I believe as OP spoken 10%.
But at @carez have you checked math if indeed there is Witholding, as it might be visual bug like we had with Canadian corps.
I have had BTI crusade some time ago:
So in any case, first thing of order, do math on dividend, if indeed tax was applied. You need to open ticket and push for resolution, I know it took me several rejections etc.
Persistency is the key.