Lots of factors at play here:
- Volthoom’s Travel Lantern was deconstructed by the Guardians of the Universe and used in their own forging of the Green Lantern rings. One of the rings, or only surviving ring, that still has a trace of the Travel Lantern is Jessica Cruz’s ring.
- Before Jessica Cruz became a Green Lantern, she was the host of the Power Ring from Earth 3. Within the ring itself was the spirit of Volthoom, or that Earth’s version of Volthoom.
- This is just me playing with the idea, but if Jessica can take control of the Travel Lantern portion of her ring, then that means she can travel from one version of Earth to another.
From – Green Lanterns Vol. 1 #25