Unable to return promise values within jQUERY DataTables api column definitions using render function - datatables

Question

I'm trying to call a function within the render columnDefs of my jQuery Datatables api. The data is returned in the console but using a return statement doesn't print the data on the table. There is also a data table warning that pops up before the table is rendered because it looks like no data is being returned.
However, when I use the second snippet to return 'nothing' - all is well and I don't receive the datatable warning.
How do I return the values from my promise?
{
"targets": [5],
"className": 'text-center',
"render": function (data, type, row, meta) {
//the if statement prevents the function from being called multiple times
if (type === 'display') {
//this if statement prevents undefined from being returned
if (typeof getJSON == 'function') {
getJSON(row.ID).then(function (val) {
if (val) {
//I see these values printed on the console for each row
console.log(JSON.stringify(val))
//but if I add return statement here data is still not printed on table
return JSON.stringify(val);
}
else {
return 'not available'
}
});
}
}
}
},
This works no errors:
{
"targets": [5],
"className": 'text-center',
"render": function (data, type, row, meta) {
return 'nothing'
}
},
The promise:
async function getJSON(deviceID) {
return new Promise((resolve, reject) => {
var data = JSON.stringify({
'deviceID': deviceID
});
$.ajax({
type: "POST",
url: MYURL,
contentType: "application/json; charset=utf-8",
data: data,
dataType: "json",
success: function (results) {
resolve(results.data)
},
error: function (error) {
reject(error)
},
})
})
}
This prevents the datatable warning but no values are rendered on the table. However, the console log is still showing the values for each row. Although, I think this defeats the purpose of using a promise:
{
"targets": [5],
"className": 'text-center',
"render": function (data, type, row, meta) {
//declaring returnValue here prevents datatable warning.
let returnValue = '';
//the if statement prevents the function from being called multiple times
if (type === 'display') {
//this if statement prevents undefined from being returned
if (typeof getJSON == 'function') {
getJSON(row.ID).then(function (val) {
if (val) {
//I see these values printed on the console for each row
returnValue = (JSON.stringify(val))
console.log(returnValue)
}
else {
returnValue = 'not available'
}
});
}
}
return returnValue;
}
},