roo_error.irb

r2.2.2 :001 > require 'roo'
 => true 
2.2.2 :002 > s = Roo::Excelx.new('./roo_error.xlsx')
 => <#Roo::Excelx:1776756266060540 @tmpdirs @tmpdir @shared @filename @sheet_files @workbook @sheet_names @sheets @sheets_by_name @options @cell @cell_type @cells_read @first_row @last_row @first_column @last_column @header_line> 
2.2.2 :003 > s.each_row_streaming do |row|
2.2.2 :004 >     p row.first.value
2.2.2 :005?>   end
"Value"
nil
 => nil 

roo_error.xlsx

I think that the value on line 9 should be "Value" instead of nil. This seems reasonable because A1 and A2 are merged together.