Scans do not complete (forking?)

Wordfence scans are not completing. They die fairly early in the process.

I did the troubleshooting steps listed in the docs, and am including my log file below.

======< Start Log File >======
[Feb 03 21:14:56:1486174496.047811:4:info] Scan process ended after forking.
[Feb 03 21:14:52:1486174492.946424:4:info] Starting cron with normal ajax at URL https://forwardky.com/wp-admin/admin-ajax.php?action=wordfence_doScan&isFork=0&cronKey=(blanked by me to post in forum)
[Feb 03 21:14:52:1486174492.917293:4:info] Test result of scan start URL fetch: array ( ‘headers’ => Requests_Utility_CaseInsensitiveDictionary::__set_state(array( ‘data’ => array ( ‘date’ => ‘Sat, 04 Feb 2017 02:14:50 GMT’, ‘server’ => ‘Apache’, ‘x-robots-tag’ => ‘noindex’, ‘x-content-type-options’ => ‘nosniff’, ‘expires’ => ‘Wed, 11 Jan 1984 05:00:00 GMT’, ‘cache-control’ => ‘no-cache, must-revalidate, max-age=0’, ‘x-frame-options’ => ‘SAMEORIGIN’, ‘set-cookie’ => ‘wfvt_431620130=5895391cad914; expires=Sat, 04-Feb-2017 02:44:52 GMT; Max-Age=1800; path=/; httponly’, ‘vary’ => ‘Accept-Encoding’, ‘content-encoding’ => ‘gzip’, ‘content-length’ => ’32’, ‘content-type’ => ‘text/html; charset=UTF-8’, ), )), ‘body’ => ‘WFSCANTESTOK’, ‘response’ => array ( ‘code’ => 200, ‘message’ => ‘OK’, ), ‘cookies’ => array ( 0 => WP_Http_Cookie::__set_state(array( ‘name’ => ‘wfvt_431620130’, ‘value’ => ‘5895391
[Feb 03 21:14:50:1486174490.622848:4:info] getMaxExecutionTime() returning config value: 20
[Feb 03 21:14:50:1486174490.607262:4:info] Got value from wf config maxExecutionTime: 20
[Feb 03 21:14:50:1486174490.590405:4:info] Entering start scan routine
[Feb 03 21:14:50:1486174490.540863:4:info] Ajax request received to start scan.