If SELinux is the issue then i think you can try to disable it temporary:
https://central.owncloud.org/t/unable-to-create-folder-redis-server-went-away/12718/3
If that works and ownCloud can write into it again then you probably need to find some one helping you to correct the SELinux rules like e.g. suggested here:
https://central.owncloud.org/t/unable-to-create-folder-redis-server-went-away/12718/6