No, Wix isn't owned by Alphabet, they do use the Google cloud platform to host customer's sites. Taking this up with Wix would be a good idea. Check out section 10 of Wix's Terms of Use: http://www.wix.com/about/terms-of-use

When using the Wix Services, you may be exposed to User Websites, User Content or Third Party Services from a variety of sources, which may be inaccurate, offensive, objectionable or illegal. You hereby waive any legal or equitable rights or remedies you have or may have against Wix with respect thereto.

If you believe a User or any Third Party Services acted inappropriately or otherwise misused any of the Wix Services, please immediately report such User and/or Third Party Service to us via this form. You agree that your report shall not impose any responsibility or liability upon Wix, and that Wix may consider such report and act upon it, refrain from taking any such action or require additional information or documents before doing so, at its sole discretion.