OPT/ CPT/ Employment

I am a F1 visa holder in united states and finished my masters in December 2018. I applied for OPT on November 2nd and 1st time my opt got denied on November 30th because DSO forgot to check one box and school got package of denial itself on 30th day(Friday 4 pm) and hence I was told from my DSO assistant to correct it and send I-765 back but she didn't inform me, it had to be sent back on 30th day or same day itself as DSO assistant wasn't aware. So I did mail that overnight package on Monday December 3, 2018.
 
After 120 days I got my RFE for OPT on April 3rd, Because I failed to submit I-765 within 30 days of the date, The reason i sent package on 33rd day was it was monday, school it self got OPT RFE on 30th day 4pm and dso assistant didnt know it had to be sent on 30 day.
 
I got notice on my RFE that I can not appeal for this decision but I may file a MTR. Currently, I have filed a MTR yesterday for this decision with my DSO's explanation that student wasnot aware of 30 day rule and she(dso) was not in office, so she(DSO) could not let him know that it had to be sent on 30th day itself.
 
I want to know that is there any chance that my MTR will be approved as lot of people are telling me that MTR will likely to fail. How long does it take to get reply of MTR? What are my options right now if my MTR fails and about doing second masters, or School can help me giving employment as h1 petitioner. and all the legal advice for solving this situation would be highly appreciated.