I think this is pretty much what I would have said if not beaten to it. I'd add, though, that the position your friend is wanting to fill is also extremely dangerous unless he/she knows exactly what they are looking for -there be sharks in them waters! The person hired for this position will have extreme control over the future of the company and every detail of how it works down to the culture.
Whatever buzzword name people settle on "consultant" is probably not what you want in that situation unless it's the rarest of type. By this I mean, the very nature of being a consultant in this business means "contractor". IMHO, generally speaking, contractors do not have a deep vested interest in the business, it's future, or it's past. That's not the type of job it is by definition.
There are consulting agencies all over the place that will claim to fix/reorganize, etc. your entire business. Very few, will call themselves a 'partner' on paper (in a contract). And that is what your friend is really fishing for here -someone who considers themselves as a partner to the the company and whom respects the values thereof.
my 2 cents.
These situations are often true.
The solution is to understand the big vision/direction in-house (even then, enterprise can turnover & new people often don't know the history). Then send out for the best "whatever" you need. Hire a few different consultants in different areas & get second opinions. More work (to manage), lower risk, more in parallel, constant feedback/results. Force consistency.
Large corps can often partner with OEMs or use specifically recommended providers (often ex employees of said OEM). Nike can call Apple for example. Depends on the size of the business/project/integration if this is an option.
Honestly, a lot of it can be common sense, standard practice & pretty straightforward too. As it is a big money earner (for anyone doing the work) there will be layers of 'abstraction' to increase the value of the service offered to the enterprise. There can be a lot of risk (depends on the company/product/tech/maturity) or it may be imagined risk.
Tech companies tend to try to behave like startups (it works) & this may be a good way to go (risk/legacy dependent).
It all depends on product/goals/resources & in-house knowledge/skills really.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.