diff --git a/harness/features/allFeatures.cloud.test.ts b/harness/features/allFeatures.cloud.test.ts
index 40b1bf74..35aba2f0 100644
--- a/harness/features/allFeatures.cloud.test.ts
+++ b/harness/features/allFeatures.cloud.test.ts
@@ -70,8 +70,7 @@ describe('allFeatures Tests - Cloud', () => {
                 })
             })
 
-            // TODO DVC-5954 investigate why these were failing on the SDKs
-            it.skip('should throw if features request fails on invalid sdk key', async () => {
+            it('should throw if features request fails on invalid sdk key', async () => {
                 scope
                     .post(`/client/${testClient.clientId}/v1/features`)
                     .reply(401, { message: 'Invalid sdk key' })
diff --git a/harness/features/initialize.local.test.ts b/harness/features/initialize.local.test.ts
index 4b63f969..b8efa64b 100644
--- a/harness/features/initialize.local.test.ts
+++ b/harness/features/initialize.local.test.ts
@@ -68,8 +68,7 @@ describe('Initialize Tests - Local', () => {
                 await testClient.createClient(true, { configPollingIntervalMS: 10000 })
             })
 
-            // TODO DVC-6016 investigate why these were failing on the nodeJS SDK
-            it.skip('stops the polling interval when the sdk key is invalid and cdn responds 403,' +
+            it('stops the polling interval when the sdk key is invalid and cdn responds 403,' +
                 ' throws error', async () => {
                 const testClient = new LocalTestClient(name)
 
@@ -79,13 +78,12 @@ describe('Initialize Tests - Local', () => {
 
                 const response =
                     await testClient.createClient(true, { configPollingIntervalMS: 1000 }, testClient.sdkKey, true)
-                const { exception } = await response.json()
+                const { asyncError } = await response.json()
 
                 expectErrorMessageToBe(
-                    exception,
+                    asyncError,
                     'Invalid environment key provided. Please call initialize with a valid server environment key'
                 )
-
             })
 
             it('fetches config again after 3 seconds when config polling interval is overriden', async () => {
@@ -158,7 +156,7 @@ describe('Initialize Tests - Local', () => {
 
                 scope
                     .get(`/client/${testClient.clientId}/config/v1/server/${testClient.sdkKey}.json`)
-                    .reply(200, "I'm not JSON!")
+                    .reply(200, 'I\'m not JSON!')
 
                 await testClient.createClient(true, { configPollingIntervalMS: 1000 })
 
@@ -180,7 +178,7 @@ describe('Initialize Tests - Local', () => {
 
                 scope
                     .get(`/client/${testClient.clientId}/config/v1/server/${testClient.sdkKey}.json`)
-                    .reply(200, "{\"snatch_movie_quote\": \"d'ya like dags?\"}")
+                    .reply(200, '{"snatch_movie_quote": "d\'ya like dags?"}')
 
                 await testClient.createClient(true, { configPollingIntervalMS: 1000 })
 
diff --git a/harness/features/variable.cloud.test.ts b/harness/features/variable.cloud.test.ts
index b276ae57..6b51e421 100644
--- a/harness/features/variable.cloud.test.ts
+++ b/harness/features/variable.cloud.test.ts
@@ -48,6 +48,7 @@ describe('Variable Tests - Cloud', () => {
                 // from the proxy server
                 expectErrorMessageToBe(error.asyncError, 'Missing parameter: key')
             })
+
             // TODO DVC-5954 investigate why these were failing on the SDKs
             it.skip('will throw error if variable called with invalid sdk key', async () => {
                 scope
diff --git a/proxies/dotnet/Controllers/Client.cs b/proxies/dotnet/Controllers/Client.cs
index 8c0eaff3..ec779d45 100644
--- a/proxies/dotnet/Controllers/Client.cs
+++ b/proxies/dotnet/Controllers/Client.cs
@@ -127,10 +127,15 @@ public async Task<object> Post(ClientRequestBody ClientBody)
                         .SetLogger(LoggerFactory.Create(builder => builder.AddConsole()))
                         .Build();
 
+                    try {
                         await task;
                         if (eventArgs != null && !eventArgs.Success) {
                             throw eventArgs.Errors[0];
                         }
+                    } catch (Exception e) {
+                        Response.StatusCode = 200;
+                        return new { asyncError = e.Message };
+                    }
                 } else {
                     DataStore.LocalClients[ClientBody.ClientId] = new DVCLocalClientBuilder()
                         .SetEnvironmentKey(ClientBody.SdkKey)
diff --git a/proxies/go/handler_client.go b/proxies/go/handler_client.go
index 6426760a..e26366ce 100644
--- a/proxies/go/handler_client.go
+++ b/proxies/go/handler_client.go
@@ -62,7 +62,11 @@ func clientHandler(w http.ResponseWriter, r *http.Request) {
 	client, err := devcycle.NewDVCClient(reqBody.SdkKey, &options)
 
 	if err != nil {
-		res.Exception = err.Error()
+		if reqBody.WaitForInitialization {
+			res.AsyncError = err.Error()
+		} else {
+			res.Exception = err.Error()
+		}
 		w.WriteHeader(http.StatusOK)
 	} else {
 		res.Message = "success"