let’s do following, if possible, stop PiHole to avoid any other DNS request on the system.
systemctl stop pihole-FTL
Once done start tcpdump
tcpdump -i any -c500 -nn port 53 or port 5335
On a 2nd SSH session, perform a test
dig @127.0.0.1 -p 5335 google.com
Stop/cancel tcpdump and restart PiHole