That is similar to my situation (except the letters reached my attorney on time, so we were able to respond to RFE on time).
We too didn't get the 2nd RFE letter (which the attorney got again) and were worried that when the letter is returned, our status will got back to RFE. But it is almost 6 weeks since it was sent and we are less worried about that now.
Btw, what is your RFER date and your current status?