Which master's for a CS undergrad wanting to break into finance?

Just graduated with a BSc in Computer Science from a Western European university and finished a Big 4 6-month internship in Financial Services IT Audit. Was offered a full-time position, but declined because I want to work at IBs and large commercial banks, ideally in risk-related, data-related roles or as a technology analyst. Quant is going to be hard, since this requires either a math background or at least a CS MSc for at least quant dev. I am also open to consulting for McK/BCG/BAIN.

Was offered a place in Imperial MFinTech course, which is basically their known MFin course but with some additional focus on applications of Python/R/C++ in finance/trading domains.

Pros: Networking in London (I don't know if that means so much nowadays), somewhat solid business school although not LSE/LBS-tier. Postgrad visa for working in the UK.

Downside: Very very expensive. Don't know if my experience is enough to land even an analyst job in the City.

Alternative: 2-year CS master's at a global T50 university in Europe (KU Leuven). More time for internships. More time for co-publishing papers related to applications of ML in finance like systematic trading with their finance department. More time to create a finance related GitHub repo.  Cheap as hell, in comparison.

Please also note that these are my two sole options. Due to a number of  reasons, I couldn't apply for other programmes and I am stuck with these two. Otherwise I have two wait 1 year again.

What would you do?