I don’t think the charger fried your gear.

If it had, it would have also fried the display unit you tried it on.

USB-PD defaults to 5V until a negotiation takes place to establish voltage and current limits. In order to have caused damage, negotiation would have to have established voltage greater than 9V.

Plenty of USB-C chargers do not supply the full range of voltages that are possible through USB-PD. For example, the Nintendo Switch’s charger is limited to 15V because that is the most the switch supports. Lots of inexpensive “phone chargers” top out at 12V.