I’ve noticed a couple of issues in the geo location query:
1) distance type: for short distances arc may be more appropriate as it gives more precision
2) units: you are using km for filter and miles for sorting

Thanks for sharing! Check out my blogpost series on geolocation searches. Cheers!

https://medium.com/@gerard-sans/finding-the-nearest-locations-around-you-using-aws-amplify-part-1-ee4d6a14eec9