If we’re to believe the Rothschild’s in the region are purebred (I’ve been told they’re not), we have 3.1 in New Zealand:
1.0 Flynn (Harold x Nathalie) 01-09-2004 at Orana Wildlife Park
1.0 Orly (Harold x Zuri) 09-11-2004 at Orana Wildlife Park
1.0 Kijana (Harold x Zuri) 30-10-2006 at Orana Wildlife Park
0.1 Harriet (Harold x Tunu) 26-11-2012 at Orana Wildlife Park
And a handful in Australia. Any offspring sired by Harold are Rothschild’s and so are the offspring of Mukulu and Twiga. One of Harold’s sons was bred to the daughter of Mukuku and Twiga at Mogo.
By my understanding, these are the Rothschild's giraffes (from the Orana/NZ lines) still living in Australia (3.7 in total):
1.0
Shaba (Ijumma x Shani) 21-08-2011 at Mogo Wildlife Park (now at National Zoo)
1.0
Armani (Harold x Zuri) 23-12-2002 at Orana Wildlife Park (now at Perth Zoo)
1.0
Ajali (Armani x Misha) 29-05-2010 at Perth Zoo (now at Werribee Open Range Zoo)
0.1
Manzi (Ijumma x Shani) 24-01-2010 at Mogo Wildlife Park (now at Altina Wildlife Park)
0.1
Penny (Armani x Misha) 24-12-2007 at Perth Zoo (now at Australia Zoo)
0.1
Tanzi (Mukulu x Twiga) 22-08-2002 at Melbourne Zoo
0.1
Shani (Mukulu x Twiga) 21-03-2006 at Melbourne Zoo
0.1
Binti (Ijumma x Shani) 24-01-2013 at Mogo Wildlife Park
0.1
Tuli (Ijumma x Shani) 00-00-2014 at Mogo Wildlife Park
0.1
Oni (Ijumma x Shani) 27-01-2016 at Mogo Wildlife Park
As far as I'm aware, the pairing you're referring to is that of Ijumma x Shani at Mogo (producing 1.4 calves), but with Ijumma's passing, the latest calves at Mogo are hybrids/generics.
(My initial knowledge of the Rothschild's lines is indebted to
@jay and the ozzoos website in the early 2000s, but any errors in extrapolations of the bloodlines since 2005ish are all mine)