Go in with a lighted magnifying glass and look for solder splash. Clean up any you might find. And recheck your recapping job and make sure there are no shorted traces next to the cap. You may have to desolder and then resolder caps to do this to check for traces that goes under a cap.
Though not Mac, I fixed a Raspberry Pi where someone got angry at it and stomped on it for some reason and crushed the USB and Ethernet Ports. Then he sold it on Ebay where I got it for $10. In soldering in a new dual USB Ports, There was too much solder on one of the pins and shorted another trace that is under the USB Port casing. The R-Pi I/O chip got hot, very hot and nether USB Port worked. Desoldering the USB Ports, removing it, cleaning the board and putting the Ports in place with less solder, the R-Pi now works great.
Good luck to you.
Though not Mac, I fixed a Raspberry Pi where someone got angry at it and stomped on it for some reason and crushed the USB and Ethernet Ports. Then he sold it on Ebay where I got it for $10. In soldering in a new dual USB Ports, There was too much solder on one of the pins and shorted another trace that is under the USB Port casing. The R-Pi I/O chip got hot, very hot and nether USB Port worked. Desoldering the USB Ports, removing it, cleaning the board and putting the Ports in place with less solder, the R-Pi now works great.
Good luck to you.