Get KV data into HTMLRewriter

I’m to trying to fetch data from KV storage into HTMLRewriter method, but has no luck - is it possible?

text(element) {

    if (this.tagname == 'loc') {
        let sefurl = null;
        if (sefurl) {
           let sefpart = SEFUrls.get(sefurl); //<-- Problem
        }
   }
 }

I can’t use await beacause text is not async function, with current syntax it returns me a promise, any suggestions?