Strange to say the least - possibly mildly scary.
On mine, the file I looked for appears to be a symbolic link to the same directory, but with a minor version on the end:
libwbclient.so.0.13
This link should be in the package:
[ root@rockout (pass 0s) /usr/lib64 ]# rpm -ql libwbclient
/usr/lib64/samba/libwinbind-client-samba4.so
/usr/lib64/samba/wbclient/libwbclient.so.0
/usr/lib64/samba/wbclient/libwbclient.so.0.13
So, first things first, try reinstalling the package, then (if successful) restart nmb,service
yum reinstall libwbclient -y && systemctl restart nmb.service
If that fails, please check for any possible versions:
ls -la /usr/lib64/libwbclient.so*
If you find one, (which is theoretically libwbclient.so.0.13), you may be able to successfully re-create the link:
ln -s libwbclient.so.0.13 libwbclient.so.0
Substituing libwbclient.so.0.13 with whatever you find.
Hope this helps!