If you always want it to open on that tab use this:
on *:DIALOG:[color:green]DialogName[/color]:init:0:{
.timer -m 1 1 did -f $dname [color:green]TabID[/color]
}
Otherwise put
did -f [color:green]DialogName TabID[/color] in the alias you want to use to open the dialog to that tab.
(Replace the green text with the correct information, of course)