You have an exact whitelist entry for bit.ly and a regex whitelist entry for the string you list above. The string is not a valid domain regex, so the only rule in operation is the exact whitelist.
Try removing both rules and then adding a wildcard entry via Domains > Domain > [x] Add domain as wildcard and add bit.ly bitly.com. This will add regex entries for both, suitably configured for the domains plus any optional subdomains.
Does it work now? Also test from any computer which uses Pi-hole with the commands
nslookup bit.ly
nslookup bitly.com
These should return the IP addresses. If they were blocked they would return 0.0.0.0.