The goal of the job is keeping large systems online and operational.
Think: systems engineering, DevOps, and sysadmin at scale - leveraging automation.
Lots of other shops still call it DevOps Engineering, Production Engineering, etc.
(I've never been in a company big enough to have one of these, so I'm just trying to understand)
Rather than focusing on making the software do X, it makes software that already does X more resilient to failure.
I think it strongly depends on exactly what you end up developing.
The quants (people who do the analysis to give buy/sell signals, basically, typically using programming for the analysis) will generally need a strong grasp of statistics and finance.
The developers that build the trading platform will need a strong grasp of exchanges and the mechanics of trading, but not really of statistics or "how the market works/reacts".
The developers that work on the reporting side don't really need a strong grasp of either. The math is relatively simple, the difficult part is handling stuff like cross trades. I.e. internally trading stocks between portfolio managers without having to hit the actual exchange (i.e. PM A wants to sell Intel, and PM B wants to buy, so you just transfer ownership instead of actual buy/sell orders). You have to attribute a profit/loss to PM A even though there wasn't a "real" profit or loss.
The SRE/ops side often doesn't require much knowledge of finance or math. The apps aren't particularly unique, and the portions of the trading flow you're expected to know aren't hard to pick up in a month or two. You aren't typically expected to have an in-depth understanding of trading strategy, or a highly detailed understanding of how trading works mechanically. Knowing that stuff probably lets you command a higher salary and title, but it isn't a prerequisite.
You don't necessarily need a better name on your CV yet. If you're just starting out, having a single financial org on there already is enough — as long as you can get good references.
Do something to skip the recruiters and talk directly to your potential colleagues.
I've been in SRE or SRE-adjacent roles at Amazon, Microsoft, Dropbox, and now a quant hedge fund (the first three in the US, the last in London). My only degree is in English lit.
Your hardest step is getting into your first job with good name recognition in the tech industry. For this, your best bet isn't certs, it's networking -- find someone who can refer you, which will get you past the automated resume screening and get your resume in front of a hiring manager, at which point your degree and certs don't matter.