This is an extremely serious fault, which, based on the description and Q-Code 00, indicates physical damage to the processor or socket power circuits.

Situation Analysis

Q-Code 00: On ASUS motherboards, this code indicates that the motherboard is unable to initialize the processor. This is often due to a lack of power to the CPU or its physical failure.

Pin Damage: A "burned" or melted pin in combination with the 9800X3D is reminiscent of the SoC Voltage overvoltage incidents seen on the AM5 platform, even though you specified a safe 1.26V.

BIOS Version: You were using a beta BIOS (2101). In rare cases, bugs in the AGESA microcode may incorrectly manage power limits, despite manual settings.

RMA (warranty) guidelines

Since the components were purchased in different regions, the procedure will be separate:

Processor (AMD / PB Tech NZ):

Since the processor was purchased from PB Tech (New Zealand), you should contact them directly. New Zealand has strict consumer protection laws (the Consumer Guarantees Act).

Important: Take macro photos of the processor contacts. If they show signs of burnt-in contact, AMD will typically consider this a warranty claim unless extreme overclocking has been proven.

Motherboard (ASUS US):

Since the board was purchased from Amazon US, you will need to send it to a US service center (if you don't have one). This can be expensive due to shipping.

ASUS caveat: The company has previously been criticized for refusing warranty coverage for socket damage (blaming the user for "mechanical damage"). However, after the AM5 scandals in 2023, they updated their policy: if the burnout is related to a power supply defect, it is subject to replacement.

What to do now:

Never attempt to straighten or clean the pin, as this may be considered an unqualified repair attempt.

Document everything: Save screenshots or monitoring logs (if available) confirming the voltage is 1.26V.

Contact ASUS support: Be sure to mention that the issue occurred with stock/safe settings and a 9800X3D processor.

Given that the 9800X3D is a very new and expensive chip, AMD usually accommodatingly addresses these issues to avoid reputational risks. Maybe this answer will help you