diff --git a/core/lib/server/pub.ts b/core/lib/server/pub.ts
index 733fa5024..468dba9b7 100644
--- a/core/lib/server/pub.ts
+++ b/core/lib/server/pub.ts
@@ -2246,5 +2246,5 @@ export const getExclusivelyRelatedPub = async (relatedPubId: PubsId, relationFie
 				).as("values"),
 				pubType({ eb, pubTypeIdRef: "pubs.pubTypeId" }),
 			])
-	).executeTakeFirstOrThrow();
+	).executeTakeFirst();
 };
diff --git a/core/lib/server/render/pub/renderMarkdownWithPub.ts b/core/lib/server/render/pub/renderMarkdownWithPub.ts
index 3f4c34b30..f7d04bebe 100644
--- a/core/lib/server/render/pub/renderMarkdownWithPub.ts
+++ b/core/lib/server/render/pub/renderMarkdownWithPub.ts
@@ -343,9 +343,9 @@ const renderMarkdownWithPubPlugin: Plugin<[utils.RenderWithPubContext]> = (conte
 					const directiveName = node.name.toLowerCase() as RenderWithPubToken;
 					const directiveVisitor = directiveVisitors[directiveName];
 					const { rel, ...attrs } = expect(node.attributes);
-					const relatedPub = await getExclusivelyRelatedPub(
-						context.pub.id as PubsId,
-						rel
+					const relatedPub = expect(
+						await getExclusivelyRelatedPub(context.pub.id as PubsId, rel),
+						`The email template included a directive containing rel="${rel}", but the pub is not related to any other pubs through this field.`
 					);
 					node.attributes = attrs;
 					directiveVisitor(node, {