If your audio interface really has a Thunderbolt 2 connection, it should work. This adapter is expressly made for this purpose according to the description on Apple's product website. It states:
"The Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter lets you connect Thunderbolt and Thunderbolt 2 devices - such as external hard drives or Thunderbolt Docks - to any Thunderbolt 3 (USB-C) / USB 4 port on your Mac.
Because it's a bi-directional adapter, you can also use it to connect new Thunderbolt 3 devices to a Mac with a Thunderbolt or Thunderbolt 2 port and macOS Sierra or later. ..."
I had bought the adapter by mistake when I wanted to connect an external SSD to a MacPro 2013 (with Thunderbolt 2). The problem was that the external SSD had a USB-C port, but this is not also a Thunderbolt 3 port.