similar for engine bay electrical fittings (due to the environment they are in) I put some silicone electrical grease on the soldered connection and then cover up with the first round of shrink wrap tubing. Followed by the 2nd layer of shrink wrap and then a top layer of the 3M Super 88 electrical tape or some split loom covering. Clearly the tape/loom can't been done in all situations.
What you did is should be fine - just mentioning as another alternative. Some also elect to use shrink wrap that has sealant inside - not sure if that's what was used here?