I would do one of two things...either go back to the doctor and INSIST he either explain exactly WHY he thinks the heel is OK when it is clearly not getting any better - AND get him to give you a time-frame on how long before he is able to walk unaided.
or secondly, get a second opinion.
Hope this helps
PS... Remember; Orthopaedic Specialists are not Gods, they sometimes just think they are, therefore do not be fobbed off