I very much doubt that to be an issue. The IP ranges from CF has been classified as CDN by Google back in 2011 [0] to not affect geo and crawl (and reputation?).

BUT, if I would be you I would definitely go for the Full SSL option so you don't share the cert with random other sites on CF.

Of course if nothing else works you can turn off CF to see if anything changes.

[0] https://blog.cloudflare.com/cloudflare-and-seo/