Linux Mint Epson Printer Fix

I’m on Linux Mint Cinnamon and my Epson WF-7830 is already added with the vendor-supplied driver, yet every job just sits in “processing”. CUPS logs hint at missing PKI pieces, specifically showing the error "cups-pki is invalid," so I suspect a certificate or dependency problem rather than a driver issue.

I’m looking for someone who really understands CUPS, Epson ESC/P-R drivers and the underlying PKI chain on Linux. The goal is simple: identify what is blocking the queue, install or repair the required package(s), and get a clean test page out of the printer.

Deliverables:
• Diagnose the PKI-related fault shown in CUPS logs ("cups-pki is invalid")
• Install or configure the missing component through apt (or another clean method)
• Confirm two successful test prints: one from the CUPS web interface, one from a normal application
• Ensure the fix survives a reboot

Please let me know which logs or commands (e.g., lpinfo, lpadmin, journalctl) you’d start with and when you can jump on a remote session. I can provide sudo access over SSH or AnyDesk. Once the printer spits out pages reliably, the job is done.