That wasn't stasis that was them trying to reintegrate them when they couldn't stop the beaming process or reverse it and you noticed they didn't try to feed what materialized on earth back through the transporter to get Sonak and the other person back.
Putting someone is stasis is sticking them in the pattern buffer until you re-materialize them.
If people are in a sort of stasis during transport, then yes, they were in stasis - they had dematerialized but had not yet rematerialized. Multple buffers are built into transporters and everyone who sets foot in a transporter is recorded. We've seen captains retrieve dna patterns from these records time and time again.
It's hardly a point in favor of your argument that the bodies weren't used to reconstruct living people. You're forgetting the alien plant that made Tuvix possible. All transporter accidents are a little different and there have been many sci-fi elements involved. What doesn't seem to change is the crew's willingness to do everything possible to retrieve their lost crewmate. They assume that transporter accidents are reversible, barring clear evidence of a fatality.
The crew acts as though Tuvok and Neelix are still alive waiting to be rescued. As the viewer, I'm going to take their word for it, especially as it matches the way transporter accidents have been treated treated throughout Trek. There's just no reason to jump to the conclusion that they're dead when the script doesn't support it.