datename(mm,events.date) will give you 'May' and 'June' from your where clause. Ordering by the NAME will put June first.

Is this what you want? Maybe order by datepart, not datename.

I know you worked around this already, but can't you replace the

ANY ( select  data_source_code

                             from  data_source

                             where data_source_code <> '30'

                          )

with 

 ( select top 1  data_source_code

                             from  data_source

                             where...