You have to download 4.9 through DAZ Connect. No way to get it any other way. Maybe you could have before with the beta, but not any longer. It's encrypted.
Not true. You can indeed download the actual 4.9 final release manually. Here's a screenshot from my Product Library :
Now, if you're looking for the BETA... yes, that can only be gotten via DIM. But the public/full version final release of 4.9 Pro is accessible, with manual download from the product library. I downloaded all of the files for it's whole bundle two nights ago. From the product library. No DIM.
The BETA 4.9 requires DIM.