“If they want to force you they have exactly one option. Give you full immunity from prosecution”
What world do you live in where only witnesses with immunity from prosecution can be compelled to testify? The court system would shut down were this the case. Or the granting of immunity would expand to absurd dimensions, making the business mostly worthless.
Fact is she will not be compelled to testify against herself; she will be asked to testify against her source. The judge would interpret refusal as protecting the source from incrimination, not herself, and she would be held in contempt of court.
What world do YOU live in? Almost every witness testifying today (besides cops, expert witnesses, etc) is there in one of two conditions. They are either voluntary (the majority), or offered a plea bargain for their own crimes, in exchange for testimony.
But the plea bargain crowd is free from forced testimony (assuming they are willing to opt instead to be tried for their own crime which they are trying to avoid)
Forced testimony is rather unusual because it is not easy to accomplish. It’s a last resort, and usually results in rather poor quality information. Sort of like if you force someone to cook you a meal. But it was very common in the USSR and Nazi Germany. It’s also in vogue in China.