int numRecords = -1 ;
Try changing that to:
int numRecords = 1 ;
Since you are requesting format YASP0100 and it's only 64 bytes long, you could probably use:
int numRecords = 16 ;
By specifying Number of records to return as -1, the list will be built synchronously. But because it's a negative 1, you haven't actually asked that any records be returned to your program. All records should then need to be returned through calls to the Get List Entries (QGYGTLE) API.
I haven't quite figured out why this API was created as an "Open List..." API. It wouldn't seem ever to be enough ASPs to demand that much effort.