He said it was from keyhunt, so unless he modified it, its straight brute force as pub key is not available for 66.

You're right. I can achieve a maximum of ~1 Ekeys/s with AMD Ryzen 9 7950X3D, but if I know what public key is.

Version 0.2.230519 Satoshi Quest, developed by AlbertoBSD
Random mode
K factor 512
Search compress only
Endomorphism enabled
Threads : 16
Stats output every 20 seconds
Quiet thread output
Mode BSGS random
Opening file tests/130.txt
Added 1 points from file
Bit Range 130
-- from : 0x200000000000000000000000000000000
-- to : 0x400000000000000000000000000000000
N = 0x400000000000
Bloom filter for 4294967296 elements : 14722.65 MB
Bloom filter for 134217728 elements : 460.08 MB
Bloom filter for 4194304 elements : 14.38 MB
Allocating 64.00 MB for 4194304 bP Points
Reading bloom filter from file keyhunt_bsgs_4_4294967296.blm .... Done!
Reading bloom filter from file keyhunt_bsgs_6_134217728.blm .... Done!
Reading bP Table from file keyhunt_bsgs_2_4194304.tbl .... Done!
Reading bloom filter from file keyhunt_bsgs_7_4194304.blm .... Done!
Total 22924448003222667264 keys in 20 seconds: ~1 Ekeys/s (1146222400161133363 keys/s)

I just modified the Make file to have -msse4.2 .
If I don't know what public key is, the speed cannot be higher than 50 MKey/s. . .