Depends how BIG of a bang it makes
If the hypothetical failed experiment caused the local Sun to detonate as a premature supernova or GRB, you would not survive merely by colonising other planets in the same solar system, or maybe even other nearby systems!
In one scenario, it's entirely possible that the technology required for interstellar colonisation is either a direct derivative or a close cousin of the world-imploding one. Like maybe the technology for a wormhole space drive or a Casimir-effect tap of dark energy to power your generation ship?
So as they say, maybe you can't to THERE from HERE?