I see from delta.dumb that I can bring in one guest into their lounges. I will be traveling to LHR and AMS, and was wondering if anybody knows the guest policies for KLM as a ST E+? I will be traveling with 2 guests, so I may have to do some negotiating, pay a guest fee, or do some lounge hopping to get both of them into a lounge, albeit we wouldn't be together.

I am also a DL Amex reserve cardholder. But on our departure in JFK, if we wanted to visit the Oasis lounge in T4, would I be able to purchase additional guest access?