Year of death RMD

Mother died Feb 2022 leaving 3 IRAs to 4 Beneficiaries ( her Children). She did not take any RMDs before she died. I know that the beneficiaries need to take her 2022 RMDs by year end. One beneficiary is considering taking a lump sum distribution from one of the IRAs instead of moving it into an inherited IRA and this lump sum will be an amount greater than her RMD requirement for all 3 IRAs.

1: With this scenario, Can one beneficiary satisfy the ’22 RMD requirements or do all the beneficiaries need to take their own percentage of her RMDs?

2: Can one beneficiary use one IRA to satisfy the total RMD requirements of all 3 IRAs?