Hi Angie
My apologies for the delay in responding.
We have added a blank alt attribute to the img element for OpenLayers markers, in keeping with the WCAG best practises.
We will be getting a patch out with this in the next few days (next Monday at the latest), if you need a pre-release please just let us know and I will arrange that.
Alternatively, you could add that attribute in /wp-google-maps/js/v8/open-layers/ol-marker.js
and do the same in the combined file at /wp-google-maps/js/v8/wp-google-maps.combined.js
. If you are running the Pro add on you will need to do the same for the combined Pro file.
I hope that helps?
Kind regards
– Perry