I encountered very high latency ping from Vultr Japan VPS
This has nothing to do with the DNS servers. Cloudflare isn’t responsible for your network connection.
Repeat this ping on
184.108.40.206 instead of Google.com. Or better: do an mtr / traceroute and paste it here
Sort of is responsible in this case. Since they do not use the edns client subnet the result from the A DNS query to google.com results in a server in London (LHR) And not in Tokyo or nearby.
Have any solution to fix? because other website are going well.
It would need to be a collaboration between CF and Google, for us the only solution would be to change DNS server. I am actually in the middle of deciding the same thing. Luckily in EU the default server is FRA, so any VPS that is there would give no problem.