There's a bug in the current version that causes the transition to fail under certain conditions. It will be fixed with the next patch.

Ok thank you,I understood that for the moment my plush will not go further.
I'm a little disappointed as I lugged this player around to see this surprise when I throw it into the teleporter to Xen.

I think you can just leave it outside or inside the plywood leading to the elevator down to the teleportation labs and grab it when you come back. Though I can't figure out how to get the Chumtoad past the part with the underwater fans.

I tried to save it where I left it near the construction wall leading to the elevator, but when I returned with Rosemberg and the whole family, when I broke the wall, my stuffed animal was gone. I too struggled to pass off the chumtoad for underwater fans

If you try to leave the toad near the plywood wall, there is dialogue where one of your companions will advise against it.
(To get it past the underwater fans, try to clear a route from a distance first)

Yeah, I know you can't leave it by the plywood wall now. If the Chumtoad is near the container when you the marines force you in, it should be hanging on the table leaning against the right wall of the container, and you can grab it when you free Rosenberg.

引用自 Cyvo：

There's a bug in the current version that causes the transition to fail under certain conditions. It will be fixed with the next patch.

Has this been patched? I still can't take it with me when opening the door to Rosenberg. And after speaking to Rosenberg, I can't find the chumtoad where I last placed it