Explanation of the error:
This Salesforce error that Gearset is surfacing is usually encountered when deploying translations using the Metadata API.
This is because of a bug with the Metadata API. If the CustomObjectTranslation and the Layout are within a Managed Package, in the CustomObjectTranslation, the Managed Package prefix is removed. This can be proved by using Workbench to retrieve the same package.
Resolution:
To work around this issue try adding the prefix to the layout.
Under the <Layouts> tag, it has to be added:
i.e.
<Layouts>Example Layout</Layout>
to
Namespace__Example Layout
To edit the XML before a deployment please see this document.
To test this in Workbench please see this series of documents.
Disclaimer: This error is returned by Salesforce directly, rather than Gearset. Even so, we offer guidance based on our combined experience with the Metadata API. Where possible, we try to help guide you to fix or avoid this error. In the case that this isn't possible, we may need to direct you to Salesforce support for further clarification.