Steve Austin is on good terms with WWE and continues to have open communication with the company. He is planning to attend Wrestlemania 30 in New Orleans on Sunday and hopes to attend the Hall of Fame induction ceremony the night before.
Vince McMahon contacted Austin himself about appearing at the WWE Network announcement in Las Vegas in February and communication between the two has remained open ever since.
As for Austin appearing on-camera at Wrestlemania 30, it's certainly possible. Vince wants to get big names from the past three decades to appear at the pay-per-view on Sunday and has been in contact with several. Given the aforementioned open communication with Austin, it's not unrealistic to suggest an Austin cameo.