I hate to sound cold-hearted, but I personally would not intervene to an extreme because if this beardie is not surviving, there is probably a reason for it.
In nature, weak or unfit individuals are produced all the time, and they serve as food for other predators. If this beardie is too weak to survive the neonatal period, it would probably be a weak adult and a poor contributor to the gene pool.
This is an especially important consideration when we are talking about species that have been inbred like crazy, like beardies. Would there be the possibility of this guy being a breeder if he reaches maturity? Was the mom in good health while she was gravid? If he has a poor immune system or is just weak overall, he would be detrimental to our captive bred Pogona pool.
Is he one individual out of the clutch that is not doing well? Is there a chance there's something infectious going around the babies? Were the parents closely related? If he's the only one not doing well (or one of a few not doing well), I would do my best to make him comfortable but not jump through hoops to ensure his survival. Would it be fair to the beardie to force an uncomfortable survival on him when he would have died otherwise?
Again, he may recover and be a fantastic pet, but if his genetics are terribly weak and he won't survive, that can happen...
Best of luck to you in any case, I hope that he does well.
You can also buy a high-calorie cat/dog food at the vet, like Hill's A/D or Medi-Cal's Recovery Formula. Mix it with a small amount of water and pass it through a strainer then try syringing it to him.
I've never personally used Jump-Start, is that the one by Fluker's? Anyone else have experience with it?
Christina
www.herptiles.net