Updating failed. The response is not a valid JSON response. specific to my browser when I include javascript in my html

I was able to insert custom html into my gutenberg wordpress editor (hosted by bluehost) and test my code by preview with no problems. I made calls to google maps and fetch() to get a list of locations to plot on the map as markers. 2 days later, I was no longer able to save any javascript changes to my post. I tried deleting the post and starting a new post. I deleted my javascript code to insert something simple like this

p id=demo/p
script
document.getElementById(demo).innerHTML = 5 + 6;
/script

It didn't matter how simple the script was, I got the error message: Updating failed. The response is not a valid JSON response.

I suspect this is a problem specific to my account/browswer/network settings because the tech support folks at bluehost did not encounter this problem when they tried to save the above script to my post. I also tried to hire someone on upwork to help me and he did not counter this problem when he got into my wordpress. I tried switching from chrome to safari and also encountered this problem.

I suspect I tripped a setting while I was running this multiple times to test. Sorry I don't know of a better test environment.

here's my original code snippet:

div id=gmap style=width:100%;height:400px;/div

script src=https://unpkg.com/@googlemaps/markerclusterer/dist/index.min.js/script
script 
var mymap;
var markers = [];

function initMap() {
    var centerpoint = { lat: 38.5, lng: -98 }; //centered around Kansas
    mymap = new google.maps.Map(document.getElementById('gmap'), {
        zoom: 4,
        center: centerpoint
    });
}
/** fetching a cvs file on the server side with a list of locations */
fetch(https://MYWEBSITE.com/wp-content/uploads/2022/03/stores.csv)
  .then(
    function(response) {
      if (response.status !== 200) {
        console.log('Looks like there was a problem. Status Code: ' +
          response.status);
        return;
      }  

      // Examine the text in the response
      response.text().then(function(data) {
        count = 0;
        console.log(fetch called successfully);
        initMap();
        processCSV(data);
      });
    }
  )
  .catch(function(err) {
    console.log('Fetch Error :-S', err);
  });

function processCSV(allData){
      const rows = allData.split('\n');
      var storename, storephone, storeaddress, storelat, storelng;
  
      for(let i=0; irows.length; i++){
        var line = rows[i];
        storename = line.split(,)[1];
        storephone = line.split(,)[3];
        storeaddress = String(line.split(,)[2]);
        storeaddress = replaceAll(storeaddress, ^, ,);
        storelat = line.split(,)[4];
        storelng = line.split(,)[5];
        createMarker(storename, storephone, storeaddress, storelat, storelng);
      }
      createCluster();
}
function replaceAll(string, search, replace) {
  return string.split(search).join(replace);
}
function createCluster(){
    var mcluster =new markerClusterer.MarkerClusterer({
    map: mymap,
    markers: markers
  });
   
 }
function createMarker(name, phone, address, latstr, lngstr) {
 var contentString = b + name + /bbrbri + phone + /ibrbr + address;
 var latLng = { lat: Number(latstr) , lng: Number(lngstr)};

 var infowindow = new google.maps.InfoWindow({
    content: contentString,
  });
 var marker = new google.maps.Marker({
     position: latLng,
     map: mymap,
     title: name
 });
markers.push(marker);
console.log(added marker to map + name);
  marker.addListener(click, () = {
    infowindow.open({
      anchor: marker,
      map: mymap,
      shouldFocus: false,
    });
  });    
}
/script
script src=https://maps.googleapis.com/maps/api/js?key=PRIVATEKEYamp;callback=initMap/script

• I have done the permalink resave
• bluehost has regenerated the htAccess file
• turned off all my plugins except elementor
• checked for mixed content, my site is all https
• checked site health rest api issues.
• switched to classic editor (then found out classic editor doesn't support javascript inserts

I'm out of ideas and I don't know why someone else, different computer, ip, browser, and maybe account can save javascript but not me.

Thanks