Have you tried to add the table 2 to subreport datasource? it should be somenthing like this
ReportDocument report = new ReportDocument();
report.Subreports["mySubReport.rpt"].SetDataSource(ds.Tables[1]);
or
report.Subreports[0].SetDataSource(ds.Tables[1]);
UPDATE
I think you can achieve it passing the contry id to the subreport with events. Right-click on the subreport object and choose Change SubReport Links, it will open this windows, from here from the available fields you select your id that refers to event table, I can imagine that's the CountryId, In the bottom part of the window leave the left part as it is, and on the right dropdown select the field to which you want to link you subreport, in your case it could be events.CountryId. In my example I used Customer as main report and Events as subreport