Re: "wouldn't the charges involved modify the trajectory"
There is a theoretical problem/puzzle on how much light you would need to optically lens light via it's own gravitational pull (from it's own energy).
I'd have to look it up again, I cannot remember if it was considered impossible, impractical or if it would happen. Does the early universe have that high a concentration of light/energy? I'd assume no due to expansion and it not becoming a singularity.