There are times when the Content Type Picker is unable to choose a Content Type because it's not displayed there:
https://travis-ci.com/github/ezsystems/ezplatform-page-builder/jobs/382976789
https://travis-ci.com/github/ezsystems/ezplatform-page-builder/jobs/377156584
https://travis-ci.com/github/ezsystems/ezplatform-page-builder/jobs/383339684
https://travis-ci.org/github/ezsystems/ezplatform/jobs/726137648
https://travis-ci.com/github/ezsystems/ezplatform-page-builder/jobs/383385522
https://travis-ci.org/github/ezsystems/ezplatform/jobs/726137648

It's hard to say what happens - we're creating Content Type the same way in every Scenario and it seems to fail randomly, seems like a cache issue.