MDT Toolkit 6.4.8456.100, 10.1909---reference multiple TaskSequenceID in Customsettings.ini

Here's the issue. Had a new version of MDT and Windows handed off to us from a group (well) above us. A newer version that acts as an all-in-one solution. However, we manage several sites and the newer version of MDT does not look for TaskSequenceID from customsettings.ini. It goes straight to the Default TS. how it's built is fine for places which manage only one site, but that is not us.

I need to find a way to force the image to a) check CustomSettings.ini first, and b) recognize references to multiple TS, so as to give imaging techs the option of deciding which naming convention to use. To better explain: With the older MDT, we had it set up so that there were four custom TS that were tied to separate sites. What would this do? If you chose Site1 TS, the machine name would be set as AMA + D/T/L + serial. In customsettings.ini, the TaskSequenceID for Site1 also included information on what OU the machine would belong to when joined to the domain, etc. Choose Site2 and the machine name would be BMA + D/T/L + serial and join to a different site-based OU. This does not work with the new(er) version given to us. It seems that it's been hard-coded so that it will only look at certain parts of customsettings.ini and the default TS. We were told of a way to use custom properties within customsettings.ini. By adding the following (simplified):

~~~
Priority=ByModel,ByDesktop,ByLaptop,TSID,Default Properties=etc. etc.

[TSID] Subsection=%BuildID%

~~~ Yes, technically this did allow us to reference a different TS aside from Default, but only one. And it didn't solve the other issue: we need it to read the rest of the relevant information in order to know Site1 machines use Site1 names, belong to Site1 OU's, and so forth. We can (probably) survive without having individual custom TS for each site but in order to automate the rest of the process we need to get MDT etc. to provide imaging techs the option to choose which site naming convention to use from the outside (and for joining to the domain, etc.)

[Site1]
OSDComputerName=AMA%ComputerTypeName%-#Right("%SerialNumber%",7)#
MachineObjectOU=Site1 Computers,OU=Site1,OU=etc. etc.

[Site2]
OSDComputerName=BMA%ComputerTypeName%-#Right("%SerialNumber%",7)#
MachineObjectOU=Site2 Computers,OU=Site2,OU=etc. etc.

[Site3]
OSDComputerName=CMA%ComputerTypeName%-#Right("%SerialNumber%",7)#
MachineObjectOU=Site3 Computers,OU=Site3,OU=etc. etc.

And so on.

I'm asking here because the team above has provided all the help they apparently can. The MDT solution was set up as a one-size-fits-all solution. And yes, I did try to modify the TS themselves by having a TS step in the Initialization phase refer to customsettings.ini, and switched out two DeployWiz_SelectTS files (vbs and xml respectively), but to no avail.