"a private party’s debts owed to the government do not justify the Government’s taking for public use of more than what is due to it. As the Supreme Court explained, under the Fifth Amendment, “[t]he taxpayer must render unto Caesar what is Caesar’s, but no more.”
That's it in a nutshell. Whatever backstop Treasury provided has been paid, and does NOT necessitate the taking of the future profits for public benefit. Takings are allowed by statute but not without just compensation.