Steps to reproduce:

1. Disable Make content available even with missing translations in Landing Page Content Type.
2. Create ger-DE language.
3. Create any Landing Page in eng-GB language.
4. Change eng-GB language in site Site Access to ger-DE in ezplatform.yaml file.
5. Translate Landing Page from step 2. to ger-DE language and publish it (disregard preview exceptions).

Result:
Exception: Return value of EzSystems\EzPlatformPageBuilder\Siteaccess\SiteaccessService::getSiteAccess() must be of the type string, bool returned

Expected result:
Preview should load without any exception.

Note:
Should be tested on v3.3 as on v2.5 this problem won't occur (but PR for v2.5 gives uniform behavior).