Aziraphale hesitated, trying to calculate the best way to go about this--and realized, abruptly, that it probably didn't matter. If the way out of the park had indeed been found, what difference would it make if Chii or this other young woman learned the truth about him? And if it hadn't...well, several people here knew already, and it wasn't as though they would not ask questions if he took Sam aside as a llama and returned with the human version.

"Of course I can," he said, smiling kindly, and laid a hand on the llama's shaggy withers, willing him back to his proper form.

((Unfortunately, distracted as he is by the goings-on in the park and the problem of Chii, the matter of clothes probably won't occur to him right away. ;) ))