I've posted this suggestion in the comments, but as it helped, I'm posting it as an answer.
By looking at Your code, I suppose You're using ExcelPackage library.
If so, I suppose You may be able to get the first cell in each column by writing:
foreach (var cell in wsRow)
{
// code to get the header cell
var header = ws.Cell(1, cell.Column);
// rest of your code here
// ...
}