500 error with rule - sub status 50 and 52

I'm trying to create a redirect rule for a specific URL but it's causing a 500 response that's hard to troubleshoot - rule is below along with IIS express log entries. Any ideas?

<rule name="SEO - Apply" stopProcessing="true">          <match url="(^.*(?i)/)(Apply.aspx)(.*)"/>          <conditions logicalGrouping="MatchAll" trackAllCaptures="false">            <add input="{HTTP_METHOD}" pattern="GET" />            <add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />            <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />          </conditions>                    <action type="Redirect" url="http://localhost:4000/jobs" />        </rule>