Secure Boot 2023 certificate update not applying

I need help confirming whether my Dell Inspiron 5570 can apply Microsoft’s 2023 Secure Boot certificate update.

Question:
Does the Inspiron 5570 with BIOS 1.14.0 support applying Microsoft’s 2023 Secure Boot certificates? If yes, what is the Dell-approved procedure? If no, will Dell provide a BIOS/firmware update for this model?

Background

Device: Dell Inspiron 5570
BIOS/Firmware version: 1.14.0
Firmware release date shown in Windows: 04/06/2023
Windows 11 Secure Boot: On

Windows shows the Secure Boot update files are present in:
C:\Windows\System32\SecureBootUpdates

• That folder includes:
  KEKUpdateCombined.bin
  DBUpdate3P2023.bin
  DBUpdateOROM2023.bin
  DBXUpdate2024.bin

However, the update has not applied to firmware.

Registry status:
WindowsUEFICA2023Capable = 0x0
UEFICA2023Status = NotStarted
ConfidenceLevel = Under Observation - More Data Needed
BucketHash = b872d0d998cd8a808992118fe9c82d73c448eadb3ff63d82e4c25598746e7f38

TPM-WMI Event 1801 says:
“Updated Secure Boot certificates are available on this device but have not yet been applied to the firmware. Review the published guidance to complete the update and maintain full protection.”

I already ran Windows Update, installed Dell critical driver updates, restarted, and manually ran:
\Microsoft\Windows\PI\Secure-Boot-Update

The task completed with result 0, but the status remains NotStarted.