WP Agents can definitely NOT issue a mileage tkt on SQ....The NW agent you got was totally mistaken.....
The only chance is if you can get a SM rep to book and hold the tkt for you and then they can request a mileage transfer from NW....There is an internal procedure for them to do this....IF SQ requires immediate tktng, (Which I have not heard), then this will not work....
Otherwise....You will need to wait until early October....