Vehicle turns on and immediately turn off on first two attempts or off when not moving at signals?

So, the engine doesn't turn on first or it starts then immediately turn off first time shows reduced engine power and interim service!
Second time it turns on then off in few seconds.
Third time turns on no issue and if stationery for a while at signal engine goes off.
I changed battery when first time it turned on then off cause battery was 30% to Bosch 95.
2 days ago, replaced it to Varta 105 again car started mechanic reset for nee battery car was perfect no issues till I went to Porsche dealer and when connected to their computer went off 2, 3 times since it was minor Porsche service I had to take it to another Porsche and when riding suddenly stopped while moving and the wheel got locked.
Unfortunately, Porsche quoted me $700 alone for full inspection and $400 for minor inspection which is hard to afford knowing it's just to find out the reason and the repair would cost me thousands.
Problem is first time I got this error a mechanic told me might be ignition not fuel pump and changed ignition coils to after market but apparently, he wasn't professional and didn't clean injector pipes and kind of scammed me as I'm a girl!
Need to say that when car turns on and off first errors are reduced engine power then engine light but since new Varta battery these errors didn't show but when went off all errors showed up on dashboard.
I really don't know what might be the reason for all these if you can help me find out!

Also, I tried running on alternator with no battery which also turned off after 2 minutes.

Hi. Thanks for your reply!

So, I been told by agency that due to an oil leak I need to change the full front wiring and crank vent heating replacement as they have seen oil leaks on the wirings and if problem continues change DME as well and quoted for parts as below which will be around $7,000.00 as the bill below is in UAE AED and very expensive for me to repair!
Is there any temporary fix for these or way to make sure which will stop the engine cutting off problem or solution to fix it with aftermarket or outside mechanic not agency?
The video shows the leaking on the wiring.
Please let me know.
Thanks

Thanks for reply.

Well, that's the problem with agencies trying to make extra money as labor fee alone here is $150/hour and outside mechanics are not really good at repairing here!
I live in Dubai and it's very hot most of the year.
The car is 2013 model 84000km not drove a lot...
Do you think the reason the engine gets cut off is this oil leak on the wiring?
Or is it DME or something else?
As I said Porsche cannot guarantee that changing wiring or stopping oil leak will guarantee solving the problem and also DME must be changed.
What's your guesses and suggestions?
TIA

Thanks.

Are ignition coil and switch the same?
As before all these the first time that car went off, I thought its battery and changed the battery one mechanic told me its ignition coils and changed to aftermarket but apparently, he wasn't very good and didn't clean injector pipes as other mechanic thought.
He did the followings and again after 2 days car went off.
Do you mean the same thing or ignition switch is different than coil?
What are those fuses on the left-hand side below dashboard called next to on off switch below it?
Thanks

Good evening,

Thanks for being helpful.
Unfortunately, I can't try yet for the option that you told me as the car is still at Porsche garage until, I decide.
So, yesterday I visited Porsche agency again to discuss their observation in person and based on what they told me as I said they need to change full wiring cables below and most probably the DME unit as they believe an oil leakage has reached DME unit that's why engine keep shutting off and showed me like images below!
However, their quote estimation is crazy as labor hours would be 15 hours which is $150x15= $2250 just labor and same amount for the original wiring.
Even cleaning wiring would cost the same as the labor fee for new one.
And DME unit would be another $3,000 and with discount total would be like $5,500.
So, I'm very tight on budget right now that even if I find the wiring from outside still the labor fee is crazy so I will see if it's possible to at least find the DME from cancelled cars garages but for wiring apparently must be genuine new part and only agency itself can fix it!
My question is, if you think there is any temporary fix, or the end of the wires can be cleaned until I sell the car in a few months?
What is your advice and best way to pay minimum amount to fix these?
Can used parts be used and do you think outside Porsche garages can be fixed or like before they will mess up as Porsche will give 2 years warranty, but others don't?
Parts that must be changed are as below.
Thanks.
Regards,
Sher

Porsche 90% think changing full wirings and DME unit together will fix the problem as first they try to save DME unit by changing wiring harness only!
I called an outside mechanic to check their rates for changing the wiring and the guy told me without checking the car in person that it might be something called PCV connector that needs to be changed! And the car was shaking a little before which I did engine mounting for but still might be related to this unit not full wiring harness!
I might get the car on Monday and if I can drive it as maybe when wires are cleaned, I can ride it for a short time I will take it to him to check and see the options!
But what do you think?
He might be right?