Possibly, but they still would have been pretty beat up and out of supplies. They may have taken the antietam effect and turned back.
But it would have been fun to see the effect on union sensitivies if they had wracked sherman like destruction on scranton, philadelphia and pennsylvania in general. Then, Some opinions here might be quite different.
Confederate attacks on Scranton and Philly were never going to happen under the best of circumstances. The most that would happen is that maybe newspapers frighten people, likely well after the confederates are gone. The geography of that portion of the country protected Scranton well beyond any serious reach of the ANV. Similarly, an effective invasion in Philly would have required an amphibious assault by the CSN, which it wasn't capable of at that point, or ever as far as I can tell. The Susquehanna river (a mile wide and a foot deep in places) effectively cut off those areas of PA as well as points north and east.
Ewell's advance men (Jenkins Cavalry) got within eyesight of the West Shore of the Susquehanna at Harrisburg. They literally rode across the property I grew up on to scout the defenses of H-burg at Bridgeport and New Cumberland. Ewell's order from Lee at that time regarding Harrisburg was, "If it comes within your means, take it". He didn't and it probably let the Confederacy live on for quite while longer post Gettysburg.
In addition to being the Capitol of PA, Harrisburg was also an important railroad junction (east west between Philly and Pittsburgh and points west, and north south from points north of NY to Baltimore, DC as well as south central PA). Trashing that junction would have been a small strategic and probably a bigger PR success, but would have risked the entire war effort of the south.
Lee sent Early south and east of Ewell towards Wrightsville, PA with orders to preserve the Columbia-Wrightsville RR bridge. I can only guess at the reason that order was given, but it certainly wasn't to move towards Philly or Scranton (I'm guessing escape route). Early failed in that task as Union forces ultimately burned the bridge. At that point in time, there was a 10 foot low head dam below the Columbia Wrightsville Bridge. Crossing there for advancement or retreat wasn't a thing without the bridge.
Lee had left the pontoons he had south of the Potomac.
For Ewell, there was one covered foot and wagon bridge called the Camelback at Harrisburg, another wooden RR bridge barely south (CVRR I think), and the wooden RR Marysville bridge several miles North of H-burg (basically in the area of today's Rockville Bridge). Union orders were to burn the camelback if the Confederates disloged the rather weak defences at Oyster Point (modern day Camp Hill) and Bridgport (modern day Lemoyne, PA).
Crossing a railroad bridge or two that you didn't control was a total **** shoot for the Confederates, and likely to lead to disaster. Slogging through a shallow but mile wide river in the face of artillery and rifle fire from the largest training camp in the Union was probably not much better either, especially considering Lee's force was incapable of occupying enemy territory for any sustained amount of time even if successful in the endeavor.
Take it as you may, but the mass of the Confederate Army trapped on the West bank of the Susky by relatively weak Union defences on the East Bank and Meade coming up from the south, makes it at least likely that the ANV is crushed between Meade and the Susquehanna, or if by small miracle, they successfully cross the Susky they get trapped there. Either is likely to lead to the surrender or destruction of the ANV prior to Vicksburg. But then again, I'm following you off topic in the point that G-burg (and by default Pickett's Charge) doesn't happen.