The engineer can still leverage this (LinkedIn, internal promotions, industry networking) without being forced into a public-facing role they might not want. When they're interviewing or networking, they can point to Vincke's public acknowledgment and say "that was my project" in contexts where it's professionally relevant, without having their personal social media permanently associated with it.
Considering Vincke was impressed enough to publicly acknowledge this individual's passion and initiative, there's no doubt in my mind that this engineer could get named credit or something that would acknowledge their role in the project if they wanted it.
But to go a bit meta: I think it's strange that we are discussing this in the context of a CEO publicly acknowledging one of their engineers (even if anonymously). Vincke is, at least in the context of the broader industry, going above and beyond. I doubt you'd see Ubisoft, EA, or Blizzard publicly acknowledging a single engineer's after-hours passion project in this way.
Feels a bit like misdirected energy, I guess? Why are we debating about the nuances of named vs anonymous credit and recognition when industry leaders don't give any?
It's like calling someone out for only tipping 10% while ignoring the guy in the top hat who's tipping 0. If you want gaming companies to get better about giving credit and recognition, you should support the companies that are at least moving in the right direction. I know it's easy to be cynical, but don't let perfect be the enemy of good.