Define colspan for table headers instead of column grouping

[bastiengrignon]

Is there a way to define colspan props for table header ? My use case is different from column grouping as I would like to have two columns in one but with only one header row :

What I would like to have :

Header
Value 1	Value 2

What I can actually make :

Header
Sub-header 1	Sub-header 2
Value 1	Value 2

So is there a way to achieve what I want to do ? Maybe I missed something in the docs 🤔