Scripting

I usually approach this (at least from a managed install perspective) by creating unique software library entries for each installer along with custom inventory rules. You can do your reporting on the actual software name, but trigger your installs based on installers software entry.

MS Lync is like this, so I create a manual software library entry for "MS LYNC x64 INSTALL", upload the MSI and plug in a custom inventory rule like this: FileExists(C:\Program Files (x86)\Microsoft Lync\Communicator.exe) Notice the install directory for 64 bit OS's. Setup your Supported Operating Systems to be just the 64 bit versions.

Create your install script or Manage install based on this entry, for all intents and purposes ignore the "real" software entry at this point. Once all of your installs are done, it will accurately reflect the total installs, where your installer entries will give you your bit based breakdowns.

Generally, I will do this with a simple batch file, for example:

:: FILE: INSTALL.CMD
@echo off
:: Check if running on a 64-bit system
if defined ProgramFiles(x86) goto AMD64
:x86
::Put your 32-bit setup commands here
start /wait x86_setup_here.exe
goto end
 
:amd64
::Put your 64-bit setup commands here
start /wait x64_setup_here.exe
goto end
 
:end
::Place any common commands here

I've not worked with DDPE much, so I'm not sure of the exact setup commands, but this gives you a general idea. You can do similar with a VBS. Then you just zip the 32- and 64-bit versions together along w/ this batch file and then in your managed install, set it to manual command, and put the name of your batch file as the command.