After reading your comment, I downloaded JPP7 and I had the same problem you had but I managed to fix it, although at the beginning the game didn't open even though everything seemed to be fine.

You can skip the steps you see unnecessary, but I will explain from 0 to make it easier to understand, and I want to clarify, $USER means "Your username", so if in your Steam Deck your user name is Kinein, $USER should be "kinein":

First open Bottles and create a Bottle type "Gaming" and let it be created.

Now, open Dolphin (KDE Neon's default file manager, the Steam Deck's DE) and make the hidden files show up.

Now, go to Downloads/ (Or wherever you have the game files) and go and copy the entire unzipped game directory.

Now, go to this exact path /home/$USER/.var/app/com.usebottles.bottles/data/bottles/bottles/bottles.

Here are the prefixes of Bottles, if when you created the Bottle in step 1 you named it "Jack-Box", you must access the directory with the same name.

Once inside the directory, go to /drive_c/Program Files and create a directory called "Games" (or whatever you want) and now paste the game files. Finally, copy or write down the complete path where the "Games" directory is.

Now, open Bottles and go into the Bottle you just created and click on "Run executable". At this point if you copied the path, simply paste it in the navigation bar or write it down or if you remember the path you can go directory by directory, because you need to get to where the game executable is.

Once in the "Games" directory, enter and open the directory where the JPP7 files are. You must click on the "X" that appears in the Dolphin filter at the bottom, otherwise you will only be shown directories.

Now, you can see all the files of the game, look for the executable called "The Jackbox Party Pack 7.exe" and click on "Run" and enjoy!

If you have any problem or I didn't explain well, don't hesitate to ask.