Need help choosing Columbia GS (Architecture) or a different school?

So I’m 22 and I’ve been in an apprenticeship for a few years for art and animation after coming out of Brown/RISD with half of a degree and a visibly useless education/portfolio/skillset. This past year I applied to two schools as a transfer student with the idea that both were the only two programs I’d want to go to if I were accepted, and both are pretty tough schools to get into so I didn’t think I’d get into both. Well, I did. As of this past week (mid July) I was accepted to Art Center for Entertainment Design and Columbia University for Architecture (School of General Studies, while I applied and got into CC initially the admissions team kept up an email conversation saying that since I’m not right out of high school I’d be a better fit for GS). Now that it’s time to choose a school and I have a few pretty big questions (how many/were any of my transfer credits accepted? can I defer acceptance as a transfer student? if I decline could I speak with an alum of the master’s program GSAPP or an advisor to see if it’d be unreasonable to go for art center and finish quickly before heading to get my master’s in a couple of years?) the Columbia Admissions office seems unreachable though! I’ve called twice during business hours and emailed the people I was emailing before with no luck. This is a major turn off and as great of a school as it seems I can’t accept not knowing if any transfer credits are being taken into account when Art Center is waiving basically every credit I have (saving a TON of money in the process).

So my questions:
-any Columbia GS students here who want to share their experience with the school? Before talking to advisors at GS and CC I assumed it was a night school for older students - I might be over the whole college social scene and dorms, but I’m 22 and if most of my classes are with people my parents’ age it’s not worth me going…I miss having peers, damnit.

-any Columbia grads of the GSAPP program (for master’s in Arch) who came from a field other than architecture or urban planning? I know it’s much harder to get into than a Bachelor’s program, and I’ll have to take a few exams that Art Center doesn’t offer (ahem, the history/theory exam), but I have a resume in architecture. 5 years of working in a firm drafting (and doing environment art for animation…ALL buildings) might not be enough to get into a master’s program without brushing up on my calculus and taking an exam or two that I’ve never needed to take, but is it stupid to think that getting in without a BS Arch is possible? I have friends who’ve gotten their master’s in Arch coming from subjects like English Literature or Linguistics - something not even closely related to art or design (or engineering/arch) but that was before my day and I know things are different now.

-What is this zero-credit course you have to take called University Writing? As someone who recently came out of a different Ivy/isn’t 40 and unaware of what college is like now compared to decades ago it seems a little pointless. Would I be essentially signing up for a semester by semester time-waster with work on top of my other courses?

-does anyone have any experience as a transfer student entering Columbia? How are they with waiving credits from another university. It’s a good school but frankly if I have a ton of related credits at a similarly high level that they won’t take, why should I spend an extra $50k+ to repeat those courses?