JSFiddle - React, Tailwind, and code Playground

HTML

<!-- Paste this where you want the article to appear --> 
<div 
    data-article="programma"
    data-param-teamcode="89678"
    data-param-gebruiklokaleteamgegevens="NEE"
    data-param-aantaldagen="100"
    data-param-eigenwedstrijden="JA"
    data-param-thuis="JA"
    data-param-uit="JA"
    data-fields="thuisteamclubrelatiecode" 
    id="clubcode1"
    style="display: none"
></div> 

<!-- This should be pasted once in the <head> for the best performance. If you already have jQuery included skip that script --> 
<script src="https://code.jquery.com/jquery-1.11.3.min.js"></script> 
<script src="https://dexels.github.io/navajofeeds-json-parser/js/dist/feed-0.0.1.js"></script> 
<script> 
feed.init({ 
    clientId: "vbvEvjxCyc" 
}); 
</script>

JavaScript

const _ElementAwait = el => {
  return new Promise(resolve => {
    if(document.querySelector(el)) return resolve(document.querySelector(el))

    const observer = new MutationObserver(ml => {
      if(document.querySelector(el)) {
        resolve(document.querySelector(el))
        observer.disconnect()
      }
    })

    observer.observe(document.body, { childList: true, subtree: true })
  })
}

const _AddLogo = i => {
  let clubcode = document.querySelectorAll("#clubcode1 .string")[i].innerText
  
  const logo = document.createElement("img")
  logo.src = `https://logoapi.voetbal.nl/logo.php?clubcode=${clubcode}`
  logo.alt = clubcode
  document.body.append(logo)
}


_ElementAwait("#clubcode1 .string").then(el => {
  _AddLogo(1)
  _AddLogo(3)
})