Engine cranks but does not start?

Recently, a client called me to fix his car listed above with a 1mz engine that cranked but wasn't starting.
From the onset, the car experienced several mechanical, as well as electrical issues. Some of those problems were:-
(1) Engine Oil consumption;
(2) Engine misfire;
(3) Engine rattling;
(4) Intermittent hard starting after shutdown;
(5) Hard to engage in drive, except engine is hot; etc.
Hence, he took the car to a garage inorder to rectify the excessive Engine oil consumption and other car problems highlighted above. Consequently, the car problems exacerbated after engine rebuild by the engineer!
The car owner wasn't satisfied with his repairs because it seems the engineer was deceitful. Although the car started after the rebuild, the problems still persisted. Valves weren't grinded after engine overhaul, engine still misfired at idle and when accelerating, etc.
The engineer whose garage the car is presently being parked, requested for another engine overhaull/ rebuild. After engine rebuild the car started, the oil was mixed with water; the engine was still misfiring, rattling, etc. It was obvious, that he didn't use durable parts to do his work.

Hence, the car owner moved the car to another garage for better repairs. The new garage suggested to the car owner that another engine rebuild is pertinent for optimal engine operation.
During my conversation with this engineer, whose garage the car is presently being parked, he told me that: "when the car was first brought in, he noticed a black smoke ( maybe he was mistaken for blue smoke, at exhaust tail at idle). When accelerating, there's a loss of power, engine bucking, popping, etc. After the rebuild, the car didn't start because the mechanic didn't unlock the car with the remote but proceeded directly to cranking the engine. In addition, the security relay wasn't actuated for starting to take place. Electrician did some wire cutting around that axis which he said was corrected to factory, opened with a remote before the car started.

Fortunately, after everything, the car started again. But there was still an intermittent misfire. What the car owner said was that, 'even when the second mechanic did engine rebuild, the car still misfired. Until he personally bypassed earth from the COP wire to the solenoids very close to the fuel injector often tightened with 10mm knot and depicted with blue and green colors on the picture. Car owner verified that the reasons for the misfire from both mechanics which still prevailed, was due to the solenoid valve that wasn't opening. That's why when accelerating it experienced a loss of power, similar to that experienced by a faulty fuel pump.

After gear oil replacement and test driven by the second mechanic, smoke started emanating from the engine bay. Precisely, from the fan relay that the car owner connected by himself. Within few minutes, the car shutdown by itself as if fuel is finished. As he tried to restart it, the car refused to. Infact, when the ignition switch was turned to Acc/ ignition position, battery and fuel light was not displaying in the dashboard/ instrument cluster. However, during cranking battery light glew faintly and start. But when throttled, it would shutdown. Electrician verified and replaced the alternator diode with a new one. When Ignition switch was turned to Acc/ ignition position, the battery and other lights came out brightly but when cranked to start engine wouldn't start again. Sadly, it still wouldn't start.

I tried to scan for DTC codes, but my scanner wasn't communicating. I checked all fuses, power and ground at obd port, those checked ok. But my scanner isn't compatible to read CAN network. There are only 4 wires intact for the obd2 port.
Furthermore, I added fuel through the intake to the engine, no change at all. I checked for spark and injector pulse. These things weren't present. But there was power to injector with just the key at ignition or ACC and COP had 1 ground and 1 power as usual.
Electrician from that garage, who also worked on the car said that he sniffed burning smell from the ECU, however personally I didn't when I went to start the car. I don't know how certain that was. Hence, I pulled out the ECU to a laptop board engineer to test the components inside. He said: "everything looks ok and test fine, however the IC he doesn't have the right tools to proceed with the test. With the ECU removed battery connected, Engine light would come ON. With ECU connected check light still comes ON.
Before I left, I checked the MAF sensor 5 wires and noticed that 3 wires were earth instead of 2 and 1 power; no ignition current/ power was available for the remaining 2 wires.
Please, what should I do to start the car?