I was ultimately able to by calling the IRS and being very persistent but patient and polite. Explain your situation and ask what they can do. The agent was able to order a copy of the installment agreement and annual statement, but those took 5 months to arrive. To get us something soon enough for our closing, the agent ended up writing a letter specifying every minute detail of my agreement and payment history, which was apparently acceptable. Good luck, hope you're able to get what you need!
