Having some insights in "certification" as such, I can tell you, that no certification program in general is thought to fill a lack of experience. If you are looking for a long term employment, this is one more reason to avoid all "tricks" which can undermine the trust on both sides. Generally, a good hiring manager prefers getting people with more commitment, loyalty and a clear will to become better than "high-fly" experts who will soon jump of the board on the next convenient occasion...
Yes, a Qt Certification proof is yet another item you can put on your CV in addition to all the projects you have done in the past. But! This is more like an external, and independent reference for your skills, but not a skill on its own!