Re: How to check if Cigna is recognized here?
Take the policy to the person from your Gemeinde/canton responsible for approval BEFORE you sign on the dotted line. And get a statement in writing from that person saying that acceptance is guaranteed before proceeding. That is the only way you can be sure that it will be accepted.
As you can see from the Zürich city app, whether an international plan is acceptable depends on your status here. Go through the steps, answering for your own situation, to get an idea if you would qualify, or not.
For instance, when we (non-EU) were here on an expat assignment we had an international plan provided by OH's employer - it was accepted because we were here on a time limited contract and fit other 'expat' criteria (paid through the home country, still on home country social taxes, etc.) and the plan was shown to provide the same or better coverage as Swiss obligatory insurance would. Once OH switched from the expact contract to a local one - mandatory after 5 years - we had to switch to a Swiss insurance provider.
FYI, OH's HR folks did all the legwork wrt the international policy. If you are looking at Cigna as part of your expat package, get your company involved.
Don't sign up with Cigna until you get an OK from the Gemeinde/cantonal responsible authority. If you do, you may find that you have to purchase Swiss insurance as well as the Cigna.
So step one - ask the agent for a written offer and copy of the full policy, then speak to the relevant Gemeinde/cantonal authority.