Very slow resolving of brave.com domains

[StevePER]

For several weeks I've noticed search.brave.com is slow to resolve and sometimes times out in my browser with a DNS error. Today I turned on query logging to try to diagnose it further and confirmed that brave.com queries are significantly slower than any other. Some stats:

• Since enabling logging, 7252 queries were forwarded to upstream servers.
• 110 of these queries were for brave.com subdomains
• The slowest 101 queries were all brave.com subdomains, with the slowest taking over 20 seconds to resolve.
• Only 2 brave.com queries resolved in less than 100ms. Every other query took over 1 second.
• Slow responses are seen with every upstream server I have enabled (cloudflare-family, quad9-doh-ip4-port443-nofilter-pri, cleanbrowsing-adult-doh).
• I have a cloaking rule for search.brave.com which is sometimes fast (< 10ms) and sometimes slow (1 to 5 seconds)

What could be causing queries to take so long to resolve for just this domain? Is there any additional logging I should enable to diagnose it further?

[StevePER]

I have the following cloaking rule:
search.brave.com safe.search.brave.com

strace seems to show that when dnscrypt-proxy goes to resolve safe.search.brave.com, it's doing so using the servers listed in /etc/resolv.conf (I did not expect this). Requests to 127.0.0.1 are failing after 5 seconds. Requests to another server on my local network succeed.