it seems what your saying is that the original IRA was rolled into inherited IRA's and no one actually has taken the cash out as yet
distributions year of death (assuming RMD's had already been required in prior year) - the beneficiaries must take the owner's RMD by the end of 2019.
don't know if there was a spouse, but it wouldn't matter because they are not the the sole beneficiary of the account. In effect they would be treated as a nonspouse beneficiary
rules for nonspouse beneficiaries:
can't treat inherited IRA as there own - ie can't roll it into any other IRA's they may have
can't make contributions to it
rmd calculation (again assuming decndent had already started RMD's)
the longer of beneficiary's life expectancy or deceased owners remaining life expectancy starting in the year following death of the owner using the single life table see IRS PUB 590-B
RMD's must be computed separately for each inherited IRA account
but the full RMD for inherited IRA's can be taken from one or more of these accounts but not from other IRA's
RMD's for non-inherited IRA's can only be taken from these type of accounts but again if there are multiple accounts the RMD for these accounts can be taken fro one or more
