After more investigation I've been able to do I verified that current Adobe technical article I've initially considered as a knowledgeable reference indeed contains partially invalid details. On my client Adobe Acrobat Reader was initially installed from its OEM (Dell) and so I guess they used some Adobe own approved setup method. During years I constantly continued to upgrade it until Reader XI MUI, that I later upgraded to Acrobat Reader DC v15.023.20070, then immediately to v17.009.20044 and then, sometime later, to v18.011.20055 and since its version continued to upgrade until current v24.002.20687 I believe that Adobe article "Acrobat Reader migration to 64-bit" needs more corrections because since registry key HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\Adobe Acrobat\DC\Installer\ do not exist, it doesn't even consider that Acrobat Reader DC MUI (32bit) when installed on an x64 bit OS will instead just use a very different registry key path (HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Adobe\Acrobat Reader\DC\Installer\) that I correctly found and that is populated with lot of registry values but not with 'SCAPackageLevel' that is described in above mentioned technical article and does not even exists.

Because of additional investigations I also did for another bug I opened some days ago, so through another technical article 'Acrobat Reader migration to 64-bit' <https://helpx.adobe.com/acrobat/kb/about-acrobat-reader-dc-migration-to-64-bit.html>, and more specifically because of 'How to identify if Acrobat 64-bit or Acrobat Reader 64-bit is installed' section contents, I've learned that presence of one of those applications can be easily detected via a dedicated Registry key value 'SCAPackageLevel' to be found into following registry path HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\Adobe Acrobat\DC\Installer\ .
Because of this it is very likely that at least 2 other similar and very specific registry key values should also probably already exist to also quickly indicate presence of Adobe Acrobat (32bit) rather than Adobe Acrobat Reader (32bit) and also of its currently installed version number.
And basically, it also seems that if for any unexpected reason, it's impossible to read contents of such involved registry key values indicating presence of Adobe Acrobat (32bit) rather than Adobe Acrobat Reader (32bit) and/or also of its currently installed version, then proper installation of 'Adobe Reader Extended Asian Language Font Pack' v23.008.20421 (32bit) via FontPack2300820421XtdAlfLang_DC.msi file will just fail with above reported error message.
And this is what has happened on my laptop where unfortunately today , I've been able to verify that registry path and key HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\ currently exists no more for unexpected and unclear reasons.
Nevertheless I do have Adobe Acrobat Reader DC MUI v24.001.20629 already installed on my laptop with Windows 7 SP1 x64 Ultimate and only earlier this morning I was able to manually update it to what should be latest/current v24.002.20687 (if interested to find additional details on other related difficulties that I've also already experienced during such upgrade process then pls also just see the other bug I opened <https://acrobat.uservoice.com/forums/926812-acrobat-reader-for-windows-and-mac/suggestions/48247154-bug-adobearm-v1-824-460-1067-getting-stuck-in-mem>).
Now, back to this issue, while it can obviously be difficult to understand how, when and why HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\ registry key may have disappeared it is also true that 'Adobe Acrobat Reader MUI' installation presence was also already detectable via HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\{AC76BA86-7AD7-FFFF-7B44-AC0F074E4100} registry path and via 'DisplayName' containing 'Adobe Acrobat Reader MUI' string and 'DisplayVersion' (both REG_SZ) containing '24.002.20687' string.
And similarly, obviously if needed, previous presence of 'Extended Asian Language font pack for Adobe Acrobat Reader DC' (from 'DisplayName' REG_SZ value) and '15.007.20033' (from 'DisplayVersion' REG_SZ value) might have been verified via registry path HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\{AC76BA86-7AD7-2530-0000-AC0F074E4100} , together with 'Spelling Dictionaries Support For Adobe Acrobat Reader DC' (into 'DisplayName' REG_SZ value) and '15.007.20033' (from 'DisplayVersion' REG_SZ value) via registry path HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\{AC76BA86-7AD7-5464-3428-AC0F074E4100}.