A few days ago I did the same, but from eTrade to Ameritrade, and it worked OK (the USD appeared in Ameritrade shortly after eTrade reported the wire transfer as completed).
However, eTrade allows for additional fields, where I added my FBO (for the benefit of) number, as provided by Ameritrade.
Still cost me $25 for the wire transfer though, but at least I was able to save in currency conversion fees (twice), currency fluctuations, and other charges related to sending back the wire from Ireland to US.