It's sounds like the package is being created correctly. When installing Acrobat DC via command line, all I used was "Setup.exe /sALL /rs /msi EULA_ACCEPT=YES" . That sample syntax they give you on that support page just doesn't seem to work at all. That page is out of date anyways, looks like all they did was slap "DC" over anything that said "12".
Once Acrobat DC is fully installed, make sure to then install the Creative Cloud Package installer from the build folder.
You shouldn't be prompted for serial number.
Regards,
Kenton