Salvador Garcia and Jenna Cross "relationship"

Salvador Garcia´s text: "Independent Anarch: While Salvador is ready, cards requiring an anarch cost You and anarchs you control 1 less blood or pool."
Jenna Cross´ text: " Independent anarch: Cards that cost blood cost Jenna 1 additional blood to pay. Sterile."

Both of them are ready.

Case 1: Jenna is using Power of One, card that cost 1 blood according to the card text. If the Salvador Garcia´s text is applied to the card first, it´s cost drops to zero and no cost is paid, because that card doesn´t cost any blood.

Case 2: Same cards but in this case both effects are applied simultaneously and Jenna has to pay 1 blood to play Power of One.

I think the latter is right, and the correct cost is 1 blood.

I would say case 1. Both happens simultaneous but they can´t so you as player chose witch one that takes place first. Just like choosing to take in blood via vessel before paying for smiling jack.

If this is the correct way I cant anser for but it feels right.