No 1099 -- what's the best way forward?

Treasury Direct doesn't send out 1099s. Instead, we must go online and look at the tax information there. My wife died in May, and it took me till January to regain control of her Tsy Dir account. It was a trust; I'm the successor trustee, which requires a new tax ID instead of her Social Security Number. New tax ID means a new account, and the new account has absolutely no tax information except for interest earned on March 15 and April 1 -- and that of course is for 2024 and no use. I have spent hours on the phone with their "help" people, who all say that I can't get a paper 1099 for 2023. (I'm pretty sure they're wrong, because our daughter died in September and did get a paper 1099 in the mail, but I couldn't convince the "help" people of that. You can't believe how arrogant and unhelpful they are.) I wrote a letter to Minneapolis asking for a paper form but of course have received no answer.

So what's my best way forward? I have an extension, but since it took eight months to change the tax ID and actually log into her account, I'm not optimistic that I'll have the information before October. Should I use a rough estimate of the figure, based on the brokerage account where the interest was deposited last year? And how do I actually enter that information -- fake up a 1099-INT in TurboTax?

Any advice gratefully received. Thanks! - Dan