Why all this discussion?
Pirate has defaulted. Tygrr.bond-p is worthless, and holders take the loss, end of story.
An uninsured pass-through will pass through losses, just as it did dividends.
As you are well aware, there is still plenty of speculation that Pirate might pay, pay in part, or be successfully sued for part or all of his debts. "Default" does not mean the story ends.
Yes, sure. The bonds have some speculative value and that's fine. If pirate makes a payout, or Pirate is successfully sued (lol), TBP holders will get some BTC. All Goat needs to do is continue acting as a pass-through of whatever comes through the Pirate pipeline.
If pirate pays out and Goat uses the money to buy back bonds, that is a breach of contract. The pass-through as described passes through as dividends.