Help porting use of v2 S3 pre-signed url to v3 in synchronous Cesium/Resource/Proxy.getURL

[charlesritchea]

We use this https://cesium.com/learn/ion-sdk/ref-doc/Proxy.html and in our implementation of getURL we use the v2 aws sdk

s3.getSignedUrl('getObject', {
            Bucket: s3Object.bucket,
            Key: s3Object.key,
            Expires: 86400 // 24 hours
        })

In v2, this is a synchronous method and works in getURL.
However in v3, The only solution I could find is async.
Is the only solution to create a PR for Cesium and hope it gets accepted?
Any ideas on workarounds, this is the last v2 use in our code.

[charlesritchea]

I just realized that generating a presigned url is entirely client side, so there really is no excuse not to have a synchronous version