I had a heel osteotomy, but from a flat foot. I also had an achilles lengthening, tarsal-metatarsal bone fusion, FDL tendon transfer (because my PTT was in stage II breakdown), and a cadaver bone wedge inserted on the outside of my right heel. (hope I'm using these medical terms correctly)
At almost 12 weeks post-op I just started Physical Therapy, and I'm seeing progress, but still can not walk without my walker. I'm 53 and was quite active until the PTT problem started 1 year ago.
Sounds like you're being realistic about your cruise. Good Luck!