Hello Luke,
Welcome to the community and I’m really sorry for the long delay in the reply.
I think way you implementing this might be slightly over complicated. If I’m correct in thinking that the content coming from soundcloud is just and iframe then you can use a custom embed as described below.
You can also use a key text field and then in your project just pass that content in to a <span> using v-html like so:
<span v-html="document.data.embed_field"></span>
This should execute your code.
Let me know if this helps.
Thanks.