I cannot get my e39 530d to start.
WHAT HAPPENED: The fuel pump in the tank failed and until I realized what its the problem on the side of the road and order a new pump and stay over 5 hours on the side of the road, I ve manage to kill the battery. Because I could not jump start it with wires I have connected another battery and after I started the engine I ve disconnected that battery and while the engine was still running I connected back my battery. So the engine run for about 5 seconds without a battery!

INITIAL SYMPTOMS: After this event I drove the car second day again and it worked but the remote worked 1 out of 20 attempts. The 3rd day it started just after a lot of engine cranking, but because I had an injector that just manage to unstuck and pop out a bit (I let the screws on purpose a bit open) I blame it on it and I disassembled the top part of the engine and changed the gasket from engine top case that I needed to change for months but I could not because of the stuck injector. After I ve assembled the engine back, but before installing the intake manifold I have started the engine and IT WORKED PERFECTLY for 5 minutes, after which I ve stopped it to install the intake manifold. After I have finished installing it I tried to start the engine and it cranks but it does not start. I also have a 2000A starter which spins the engine like its popcorn and nothing.
TESTING:
-I have took from my old car the Camshaft sensor, the MAP and the MAF sensors and it still doesn t starts.
-I ve checked the fuses in the glove-box and the fuse-block nexts to the ECU.
-I ve uninstalled the intake manifold and nothing, then I ve untied a pipe from an injector a bit and I have pressure from the electric pumps but it seems that the pressure doesn t increases when I crank the engine.
-I have got a BMW Scanner v1.4 interface and checked the EWS, but that one is fine. At the DDE it shows just the glow plugs and electric fan as persistent errors.
-I also checked with my old car ECU and gearbox computer and it detects the same errors and it cranks but does not starts. My old car had the ECU remapped and somehow it accepts the EWS and key chip from my actual car, but I have never tried it before to see if it actually works on this car.
WHAT I HAVE:
-BMW Scanner v1.4 interface
-A spare parts car that is identical for testing different modules.
-A INPA interface but I cannot get over that IFH-0003 error even after installing another version of Windows 7 32bits. I tried another version of the INPA software that doesn t give that error, but instead that one gives the "Continue Script ?" error and its also in german 95%.

Please help me if possible, my village will be in full lock-down in a few days and I have to get in the city to buy food while I still can.