Enable the trace feature on the printer, do a scan, stop the trace and download it, open it in Wireshark and see what is happening.
But SMB 1 would rarely be on 445, it is typically on 139 and uses Netbios over TCP/IP, and a firmware update would not be expected to fix SMBv1, because it is all but eliminated in most every OS (MS even killed it in Windows XP, years after they stated it would no longer receive updates)
But since you have multiple devices, and assumed to the same location they are all scanning or it would not have been worth mentioning, then you can wireshark a device doing a scan that works, vs this one that doesn't and compare them side by side (literally) on your PC. Either the 7970 is using different information to scan, or it is in some way corrupt, and will need to be altbooted to wipe it and start from scratch
I have a WC7970i at software version 073.200.058.25300 and upgraded the firmware from support 9/27/18 due to login issues in network scanning when the server was updated. All of the other xerox's nework scanning stopped working but after upgrading firmware everything worked except the 7970 which still will not network scan. Any other patches going to be released or any other suggestions. Port is 445.