The one in the middle looks the most like Jackson at that time frame and could very well be him.
blackbetsy.com has a photo of him in an As uniform with Strunk and another player from 1909...Id email Mr Nola about it if I were you he would probably be able to tell you if Jackson was in El Paso with the As in 1909
http://www.blackbetsy.com/photosTheEarlyYears.html
I was assuming you meant the one in the middle might be Jackson bc the other two are easily identifiable.