When making this request:
```
https://en.wikipedia.org/w/api.php?action=mobileview&format=json&noheadings=true&page=Ancillae Assumpta Academy&prop=sections|text|lastmodified|lastmodifiedby|languagecount|id|protection|editable|displaytitle|thumb|description|image|revision§ionprop=toclevel|line|anchor|level|number|fromtitle|index§ions=all&thumbwidth=640
```
I get a response containing:
```
"image": {
"width": 2592,
"file": "FLW Beth Sholom exterior.jpg",
"height": 1944
},
"thumb": {
"url": "//upload.wikimedia.org/wikipedia/commons/thumb/e/e4/FLW_Beth_Sholom_exterior.jpg/640px-FLW_Beth_Sholom_exterior.jpg",
"width": 640,
"height": 480
}
```
Update with summary of comments below:
This image is from the "Cheltenham" template which is in the article but not visible in the MobileView HTML.
This query returns the images:
```
https://en.wikipedia.org/w/api.php?action=query&format=json&prop=images&titles=Ancillae+Assumpta+Academy
```