HP network printer is visible, but will not connect with HPLIP, and will not print with CUPS

I'm currently running Ubuntu 21.10. I have a legacy all-in-one printer (HP OfficeJet Pro 8500). It is connected to my home router. I have its IP address, and I can connect to its embedded web server, check ink levels, etc.

I tried connecting to the device first using HP Device Manager, because I hope to configure the scanner as well as the printer. HP discovered the device on my LAN. The Device Manager prompts me to Click Next to continue. About 3 seconds after clicking Next, the Next button changes to read Add Printer, but nothing else happens. Clicking Add Printer results in another 3-second pause, but still, nothing else happens. Clicking Back and Cancel are my only options to proceed. No device is added.

Next, I tried falling back to CUPS. I can discover the printer, and this time I can also add the printer. (I suppose I might have to deal with the scanner separately.) But when I try to print a test page, the test page goes into the queue and never prints. If I look at the printer's Status on the Print Queue page, it reads, "Processing - Not connected?"

EDIT: I just happened to try invoking hp-setup from the Terminal. This brings up the Device Manager Setup Window. I can see a Python exception thrown when I click Next. I get a file permissions error, which happens to be a SILENT error on the GUI (the very worst kind). Here's the complete terminal log output with the traceback:

HP Linux Imaging and Printing System (ver. 3.21.12)
Printer/Fax Setup Utility ver. 9.0

Copyright (c) 2001-18 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Searching... (bus=net, timeout=5, ttl=4, search=(None) desc=0, method=slp)
Traceback (most recent call last):
  File "/usr/share/hplip/ui5/setupdialog.py", line 1348, in NextButton_clicked
    self.showAddPrinterPage()
  File "/usr/share/hplip/ui5/setupdialog.py", line 729, in showAddPrinterPage
    self.readwriteFaxInformation()
  File "/usr/share/hplip/ui5/setupdialog.py", line 1171, in readwriteFaxInformation
    self.fax_number = to_unicode(d.getPhoneNum())
  File "/usr/share/hplip/fax/pmlfax.py", line 146, in getPhoneNum
    data = utils.printable(self.getPML(pml.OID_FAX_LOCAL_PHONE_NUM)[1])
  File "/usr/share/hplip/base/utils.py", line 959, in printable
    return s.translate(identity, unprintable)
TypeError: str.translate() takes exactly one argument (2 given)
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 153, in apport_excepthook
    with os.fdopen(os.open(pr_filename,
PermissionError: [Errno 13] Permission denied: '/var/crash/_usr_share_hplip_setup.py.1000.crash'

Original exception was:
Traceback (most recent call last):
  File "/usr/share/hplip/ui5/setupdialog.py", line 1348, in NextButton_clicked
    self.showAddPrinterPage()
  File "/usr/share/hplip/ui5/setupdialog.py", line 729, in showAddPrinterPage
    self.readwriteFaxInformation()
  File "/usr/share/hplip/ui5/setupdialog.py", line 1171, in readwriteFaxInformation
    self.fax_number = to_unicode(d.getPhoneNum())
  File "/usr/share/hplip/fax/pmlfax.py", line 146, in getPhoneNum
    data = utils.printable(self.getPML(pml.OID_FAX_LOCAL_PHONE_NUM)[1])
  File "/usr/share/hplip/base/utils.py", line 959, in printable
    return s.translate(identity, unprintable)
TypeError: str.translate() takes exactly one argument (2 given)

Any advice is appreciated, thanks!