How to inject a voicemail recording into a softphone

I work as a collections agent and I make 300ish calls a day, 99% of them involve leaving a voicemail. I am trying to figure out a way I can inject a pre-recorded voicemail message into my work computers soft phone while still be able to use my wireless usb headset.

The problem I am running into is I am not able to change any audio setting on my work computer. I originally tried a USB soundcard, but as soon as I plugged it in, my wireless headset would stop working because the audio settings would cause both my mic and headset inputs to change to the sound card.

I used AI and it suggested using a TRRS adapter, convert trrs to trs, then use a trs to XLR adapter. The problem is, every single trs to xlr adapter I can find is sending the audio the wrong way.

Is there anyone that can point me in the right direction to complete my setup? I dont care what method is used, as long as I am still able to hear audio through my wireless usb headset.

TIA