As explained clearly in previous posts, the problem was primarily the Velocity web site login step, not the Estore itself. Collinson Group is the likely operator of this part of the infrastructure, as already discussed.
None of that is relevant whatsoever, that's not how IT works in 2023. It's all about using cloud services, *particularly* for short-term promotions like this, as you can scale up to meet the demand without paying for long-term capital infrastructure. No one is running any cables , you're living well in the past if you think that's how things operate these days. And people are delusional if they think they can handle this kind of load in-house themselves (unless they really spend millions and millions on infrastructure for a one-time promotion, which would be incredibly stupid when a specialised content delivery network / cloud security company can handle it for a fraction of that cost).
Please read posts 365 onward on page 19 for how this actually works.