Has anyone consulted for Atheneum?

About 3 weeks ago I got an email over LinkedIn from a representative from a company called Atheneum.
They are a Berlin Germany based operation specializing in connecting business clients with others in specific fields.

For example, I was originally contacted to discuss with a client of Atheneum the current Non Destructive wire rope we have in use for our mine shaft.
Another mining company had reached out to Atheneum to find out what the industry norm is for this particular piece of equipment.

Atheneum offered me $250 USD for a phone call with the client.
I originally said as long as it does not go over an hour, then it's less what I usually charge for an hour consultation.

I looked into Atheneum and found a lot of negative reviews.
People claiming they had never been paid, this and that.

Well, I got ahold of Atheneum and told them I decided to not be part of their services due to the abundance of reviews I read.

Today I got another offer from them. Asking me to consult for a startup wishing to understand the challenges associated with drifting in a hard rock mine.
This offer is $300 USD for a 45-minute telephone call.
But this time it's from the "Manager" of Atheneum and basically he says:

"Atheneum is under new management now. However, I can definitely appreciate your skepticism and I would like to take this opportunity to address your concerns. Could we have a quick call? If so, I will call you straight away if you reply within the next 10 minutes (as it’s already 6 o’clock in Berlin). "

I missed the 10-minute window there, but I replied for him to call me tomorrow morning to discuss.

Now, I've never dealt with a 3rd party arranging consultations before. I have always been contacted directly from the client and gone from there.
I'm wondering if anyone here has dealt with or had heard of this company before.
The reviews I quoted are from a few years back.
So if they are still running, it's not out of the question that they perhaps are under new management and this guy is looking to clear Atheneum's name.
I'm hoping someone here has some input on these guys.

Off the top of my head what it sounds like is that this company is running yet another mining scam and hope to use legitimate folk like yourself to convince "marks" of the company's legitimacy.

Could be wrong.

a reply to: The GUT

And that's what concerns me the most, is having my name attached to some sort of MLM scam or something of the sort.