Actually, I had people disagreeing with me on here that it was given back to Isho.
I do believe he buried it however, I also believe his story of not remembering where has to do with BIG Iisho. No way Iisho would touch or go near any of them knowing what was going on and all the media attention. Probably warned DM/MS to stay away. If there were any text's or convo's we'll be hearing about them eventually. We also forget that there is video evidence available from MS's stay at MM's sisters apartment that has probably been gone over extensively. With phone records and video evidence they may or may not be able to tell us when he snuck out to do this but when he did not.