I agree with the above.
Of course, the key word is 'should'.
That said, if you could afford a little extra effort/time, you could demo this to yourself.
IOW, paint up a scrap piece of wood as you have your project...same paints, etc. Hopefully you have some scrap pieces of the original decal...even if they're only the manufacturer's name, a color alignment target, even a piece of clear film. Apply it to the scrap as you did the project piece (setting solutions, etc.) Then, when it's all thoroughly dry, try the Clearcoat. If it works there, it will assure you of success on your project.
FWIW, always...
KD