XLSX processing does not keep font rendering information of a complete cell

[GVogeler]

A cell completely formated as bold
(probably <si><t>High Ward</t></si> in the xlsx source)
results in cells with not rendering information:

(while inline formatting is converted into hi/@rend).

I assume that the problme lies in https://github.com/TEIC/Stylesheets/blob/dev/xlsx/xlsxtotei.xsl#L181-L193 where there seems to be only a mechanism to resolve date formats and not the pointers to /styleSheet/fonts/font via @fontId or other style information (alignment, number format, fill, border).