Okay, I was able to figure it out. The old VMware article had at least somewhat where to look in the with the Exchange server IIS settings, the best reference was from Microsoft in regard to client-specific message size limits that can cause this issue:

Configure client-specific message size limits in Exchange Server 

The ActiveSync commands (followed by an iisreset) immediately got things going, even the failed sends from prior were sent by the device successfully:

%windir%\system32\inetsrv\appcmd.exe set config "Default Web Site/Microsoft-Server-ActiveSync/" -section:system.webServer/security/requestFiltering /requestLimits.maxAllowedContentLength:51200000
%windir%\system32\inetsrv\appcmd.exe set config "Default Web Site/Microsoft-Server-ActiveSync/" -section:system.web/httpRuntime /maxRequestLength:51200
%windir%\system32\inetsrv\appcmd.exe set config "Exchange Back End/Microsoft-Server-ActiveSync/" -section:system.webServer/security/requestFiltering /requestLimits.maxAllowedContentLength:51200000
%windir%\system32\inetsrv\appcmd.exe set config "Exchange Back End/Microsoft-Server-ActiveSync/" -section:system.web/httpRuntime /maxRequestLength:51200
%windir%\system32\inetsrv\appcmd.exe set config "Exchange Back End/Microsoft-Server-ActiveSync/" -section:appSettings /[key='MaxDocumentDataSize'].value:51200000

It should be noted that it's been observed that the settings may revert to default after an Exchange CU, so keep note of what changes you've made to reapply them