The Gharial consumed the crimson sphere as the effects of the syringe's solution took action. The solution would generally place an animal in a state of suspended animation while she would enter its mouth to take control.
But, this wasn't limited to her alone. Others too could do that, provided they could become small enough to enter the bodies of animals. This was why when she obtained this power, Xuna felt that it was perfect for her as a spy.
After all, it wasn't just her that could infiltrate enemy areas using it but could also bring her allies in the same way.
And now, what she had been attempting was something similar.
By dropping the blood of all the people in the vat, she was storing their genetic information. While the collected blood dried, the information was concentrated further. And the presence of the healing rod was to ensure the genetic material didn't begin breaking down as it did naturally.