For other org's out there looking to grow your Eng team I highly recommend trying Triplebyte! As a user I think it's super intuitive with great candidates - also did this case study with them (Zeal <> Triplebyte)

So they hire a special agency which jumps from LinkedIn to GitHub to actually verify their needed tech stack.

That's actually a cool business model, because we know that hiring agencies are not able to parse GitHub, and thus are not able to check the needed tech stack.

You could also go the easier route, but big companies prefer the slow, expensive ones.