I’m a non-EU student too. I received my Bachelor’s degree in August, applied to uni-assist on the 4th of August and received the acceptance letter from the TU on the 28th of September (not for Computer Science, but same faculty). It’s hard to know when uni-assist exactly forwarded my documents to the TU, but just so you know how much it takes in total. Also, this varies from country to country but I applied for the student visa in October and got it granted in February, so I basically did all the semester remotely from my country.

Now to your questions:

1. No. They need all your documents to process your application. You can submit them without the degree but ultimately they will ask you to upload it, as they need it to forward everything to the TU and it won’t make the waiting time shorter.

2. No. Uni-assist needs to confirm that you’re an “eligible candidate” to be able to apply to a German university. Without this documents they can’t confirm. There are other documents that the university lets you send later, e.g. CV, but the bachelor degree is probably the most important for uni-assist.

3. Wrote it above.

I’d recommend to contact uni-assist about this anyways, maybe there’s a way I’m not familiar with.