Faith healer or fake healer?

This is what I understand from this Brother Eli's video:
https://3speak.tv/watch?v=fatimajunio/hilembcm
Apostle Paul was firm in advising the Corinthians Christians in 2Cor. 11:13 to be careful of false apostles, and deceitful workers who fashion themselves as if they are apostles of Christ.

In verse 14, he reminded them that Satan himself is transformed into an angel of light. And in the same 2Cor. 11, verse 15, he said it's not a strange thing if the ministers of Satan also are transformed as ministers of righteousness.

And so, fake healers behave as if they are faith healers, using the name of Christ, and go about deceiving many people. As they do all these supposed miracles and healings, they will be surprised by the answer they will receive from our Lord Jesus Christ on the judgement day.

In Mt. 7:15, Jesus first warned his listeners to beware of false prophets. And in verse 22, he said many will say to him that they used his name to prophesy, and cast out devils, and did many wonderful works. But, he will reply that he knew them not because they were workers of iniquity.