I'd be a bit concerned about offering my sensitive info to an entity that doesn't respond. There's a lot of "spoofing" going on (aka hacking info by creating or hijacking websites that look legit).
Companies are also being gobbled up by hungry competitors by the mouthful right now,
One way to know (and protect yourself in case of a breach) is to reach out to the corporate admin to confirm the details.
When I search Sedgwick and marketing research or mystery shopping feedback is that it's a 3rd party claims admin for worker's comp.
Hope you're able to get clarity.