Since the VIA code for the K5 Pro ISO is still awaiting approval from Github, it is not yet automatically recognized, so you will need to manually download and import the K5 Pro keymap.
Please download the keymap JSON file below. Connect your keyboard and device with the provided cable, and toggle the switch to cable mode. Open VIA, click on the "Show Design tab" on the "Settings" tab, and drag the JSON file into the “Design” tab on VIA to get the K5 Pro keymap working on VIA.
K5 Pro Keymap JSON Files