I solved the issue! I was having the same problem of not being able to sync my voice memos to iCloud but I just found a way to do it. Apparently, the voice memos don't sync because they are at a low bitrate (mine was 64 kbps) and iCloud won't save songs or voice memos at that low of a rate.
Here's how I did it:
1. First, I emailed the voice memos to myself as an mp4 to get them off of my iPhone and I saved them to a file in my music folder.
2. Next, I downloaded a free program on CNET called "Free MP4a to MP3 Converter 7.1).
3. I then selected and converted each voice memo to an mp3 WITH A BITRATE OF 256 (the higher bitrate is the key).
4. Lastly, I uploaded the new mp3 file to iTunes and iMatch synced it to iCloud
It's a long process but if you want the voice memos synced to iCloud bad enough, this way works for me. I haven't seen anyone post a solution for this problem so I will try to post this on several different places. Hope it works for you!