the estate can pay the estimated taxes and then use Form 1041-T to report it to the beneficiaries.
https://www.irs.gov/pub/irs-pdf/f1041t.pdf
The Estate is going to file a Form 1041 and Form 1041-T is one of the attachments. Further the Estate should be sending a Form K-1 to each beneficiary which gives each of them the details of the income to place on their personal tax returns and the FOrm 1041-T shows them the payments they can put on Line 25 C of their personal Form 1040.
While there may be one 1099 to reflect the Estate activity, there needs to be a K-1 for each beneficiary.
Might be worth hiring a tax accountant as this can be a complex undertaking if this is a 'one and done' situation that you have never done before (and may never do again). It can be tricky and if there is that much money involved, best to hire an expert; it'll avoid a lot of headaches and ensure there are no mistakes - family harmony can be a delicate situation to navigate and an expert will give everyone confort that is was done correctly and accurately.
