Fill Datagridview intercalating data from 2 queries

[RH+]

I have a Datagridview, It will have pairs of lines:
first line: requested customer
second line: assigned quantity for that item for that customer

Something like:
CUSTOMER-ITEM-VARIATION1-VARIATION2-VARIATION3-VARIATION4
Cust001....-120.-......10........-.........0.......-........8........-.........1
Cust001....-120.-........0........-.........0.......-........0........-.........0
Cust002....-120.-......15........-.........7.......-........2........-.........0
Cust002....-120.-........6........-.........0.......-........1........-.........0

The second line will have numbers if other table has information about that customer reservations, or will be in 0 if not.

I can load the first line of each pair, with the data of the "requested" items loading a datagrid with a datatable.
The problem is that i don't know how to add the second line.
Thanks!
And sorry if something is hard to understand, english is not my first languaje.