I'm a bit confused about the last part: "... Then, either you draw 2...". Does one of the effected players get to draw 2 cards if the test succeeds?

“Then” requires the preceding text to successfully resolve, which in this case is the skill test failing.

So if the skill test fails you have two choices after resolving the effects of failure against the investigator who committed Self-Sacrifice:

• The player who committed Self-Sacrifice draws 2 cards.
• The player who performed the skill test draws 2 cards.

If the skill test succeeds then nothing happens.

"Then" means you only do that text if the previous part completes. So you only draw the cards if the test failed.

So it's like a weaker take heart? I see.

1 hour ago, django042 said:

So it's like a weaker take heart? I see.

Depends on what you're using it for. It also moves the effects from the original character to the one committing the skill, which can be useful.