To put your mind at ease, all brands of M&P clear/extra clear soap are either slightly milky looking or yellowish when they arrive. When you melt them and it re-hardens it will look MUCH better.
SFIC is the highest quality M&P soap I know of and it's clear shaving soap is even more yellow looking when it arrives than is their extra clear soap, nevertheless I still end up with a beautiful (highest quality) product. I actually use the shaving soap for my embeds and just to negate any possible yellow tint I add a fraction of a drop of ultramarine blue so the resulting impression is that of clear glass (which when seen from the side shows a hint of green). Here is the best possible proof that this technique works (and all these soaps made with SFIC's even more yellow looking shaving soap):

please pardon the large image
You'll notice that some of the soaps look more clear (less blue tinted) than others. That's because they were different batches and I used less blue. The long term result when using too little blue is the possibility that the soap may turn slightly yellow after a few months. So I've learned to adjust the level of blue tint used for the best results -- long term.