Whenever I try to deploy Drupal using the Web Platform Installer command line using a parameters file, it always detects/chooses the server type of MSSQL even if we are using MySQL Parameter names.

Other apps are not having this problem, it seems specific to this app which suggests a problem with the package.

Example parameter names generated / used in the .app file:

Drupal w/ MSSQL:

Application Path[@]
dbServer[@]
dbName[@]
dbUsername[@]
dbUserPassword[@]
dbAdminUsername[@]
dbAdminPassword[@]

Drupal w/ MySQL:

Application Path[@]
mdbServer[@]
mdbName[@]
mdbUsername[@]
mdbUserPassword[@]
mdbAdminUsername[@]
mdbAdminPassword[@]

The following error shows that even though the app file is specifying MySQL parameter names it is erroring trying to find MSSQL parameters:

C:\tools\WebPICMD>WebpiCmd.exe /Install /UseRemoteDatabase /AcceptEula /Application:AcquiaDrupal@"C:\tools\WebPICMD\Acquia Drupal 70.app"

The software that you obtain using the Web Plaform Installer Command Line Tool is licensed to you by its owner.  Microsoft grants you no rights for third partysoftware.
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Please
choose a database for 'Acquia Drupal 7'
Selected database: 'SQL'
The following software is going to be installed:
EULA: 'Acquia Drupal 7', which is owned by 'Acquia.com', will be downloaded from 'https://network.acquia.com/files/downloads/acquia-drupal-web-deploy-7.14.14.5808.43909.zip'.
The license agreement to 'Acquia Drupal 7' may be included with the software.
You are responsible for and must separately locate, read and accept these license terms.
Accepted Eulas.
Starting Installation
Started downloading products...
Started downloading: 'Acquia Drupal 7'
Downloaded: 'Acquia Drupal 7'
Reading Application Parameters from : C:\tools\WebPICMD\Acquia Drupal 70.app
Installing Application against IIS...
Started installing Products...
Started installing: 'Acquia Drupal 7'
Install completed (Failure): 'Acquia Drupal 7'
AcquiaDrupal : Failed.
Missing source parameter 'dbUserPassword' (Password for the database user name.)
. This must be set for successful synchronization.

Verifying successful installation...
Acquia Drupal 7                                    False
    Log Location: C:\Users\AppData\Local\Microsoft\Web Pl
atform Installer\logs\install\2012-11-13T17.52.18\Acquia Drupal 7.txt
Install of Products: FAILURE
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