Are those intermediaries who go abroad for medical treatment reliable?

Our family just went to Germany. I'm telling you, don't listen to what the intermediary says, just stick to two points. First, resolutely do not hand over medical expenses to the intermediary, you must pay for the hospital yourself, and only pay the intermediary service fee; Second, keep reading emails. Many of their contacts with foreign countries are by mail, regardless of documents and the like, they can be forged, and there are no formal documents. Whether they really contact a regular hospital depends on whether the mailbox is the hospital website.