Could Prince Philip have remained in naval command?

Could the Queen have kept Prince Philip in naval service with another command or a Dartmouth appointment?

Theoretically yes, but Philip chose to leave that career path so he could support Elizabeth.

A shore command or training appointment could theoretically have kept Philip in naval service. That option would have limited the help he could give Elizabeth once royal duty took priority. He chose to make supporting his wife his first responsibility, so the decision reflected personal and constitutional duty rather than a lack of available naval work.