MIBG With Dinutuximab +/- Vorinostat

Patients will receive 131I-MIBG on day 1. 131I-MIBG dose will be based on the dose level assigned at the time of patient registration

Dinutuximab is given intravenously on days 8-11 and 29-32 of therapy. Dinutuximab dose will be based on the dose level assigned at the time of patient registration.

Vorinostat will be given on day 0-13. Vorinostat dose will be based on the dose level assigned at the time of patient registration.

Sargramostim (GM-CSF) will be given on day 8-17 at 250 mcg/m\^2

Potassium iodide will be given by mouth at a dose of 6mg/kg 8-12 hours prior to infusion of 131I-MIBG on Day 1 and then 1mg/kg/dose by mouth starting 4-6 hours after completion of MIBG infusion and continuing every 4 hours on protocol days 1-7 and then 1mg/kg/dose by mouth once daily on protocol days 8-45