Well, it looks like Albert V was definitely born in England (in Weymouth, see freebmd), but they may have left soon after that.
Do you have the marriage certificate of Emile and Lily from 1916? That should tell you Emile's father's name (and maybe show if Joseph Loquet was a witness, although I can see only one Joseph Loquet and he married down in Kent, not in Durham).
The problem is that you will not find ship lists for within Europe and it doesn't appear that there are naturalisation records for this family that I can find (probably Emile didn't; don't think Albert would have needed to). You might try tracking down Emile's death and seeing if there's any reference in a death notice/obituary to family in Belgium, and possibly Albert's as well (might for example mention something about his life pre WWII).