I missed this posting and just saw it this weekend. It's not likely our John Solomon are the same. The date are all wrong but you are correct with the name change idea. Many of the the immigrants found their names changed to Solomon from Salmoun or even Slemen. Simon could be just another Ellis island derivation.
As you dig deeper you may find the first name changed also. In Lebanon he would have been Hanna instead of John. Good hunting.