Originally posted by FSHerrante:

You can activate the dev commands temporally and fly to your boat. This is a trick, i know, but sometimes is necessary if you really want to recover your boat or loot from unacessable location without spend many resources and time.

The trick I usually use is to just back up all the saves in a separate folder and restore said backup if I end up dying. Like Caves of Qud but more tedious.