The answer is this simple bit of code (https://gist.github.com/hereswhatidid/a67dc3697a481c223bdced42586f6664):
if( window.acf ) {
window.acf.addAction( 'render_block_preview/type=accordion', function( $elem, blockDetails ) {
initializeElement( $elem );
} );
}
And this bit from this article helps if you change the namespace to target your block(https://www.billerickson.net/building-acf-blocks-with-block-json/):
“If you use a namespace other than “acf/” you need to use the full block name in the callback, so: render_block_preview/type=cwp/tip”