I’m sure I’ll get the names of the menus wrong as it’s presumably all translated from French so sounds a bit odd anyway, but after the “computer test” then “multiplex network” test I’d be going into “petrol injection”. Do a “fault test” to see any DTCs. A red circle is a fault currently occurring, flashing orange is a stored DTC IIRC. I guess with the engine running I’d expect to be able to read RPM under a menu called “list of parameters”. Maybe there’s a “I’m at TDC” flag under “list of statuses” but I highly doubt it. If you think about how a Hall effect sensor works on a 100 tooth wheel (made up for easy numbers) TDC is identified by detecting one “long” pulse amongst 99 short pulses per revolution. But if we’re idling at 1000rpm (16rps) and you have 100 teeth on your flywheel then the long pulse is 0.0006 seconds which is frankly absurd anyway so yeah... you’re never going to see something that fast without an oscilloscope.
I don’t mean to teach you to suck eggs but like any diagnostic software Clip is just a tool to point you in the right direction. It will tell you exactly what is happening (e.g. short to ground for a specific sensor/motor/module etc) but it obviously can’t be expected to tell you why (e.g. broken wiring loom vs internal fault on a sensor).
I don’t know if you’ve just guessed TDC sensor or already narrowed it down, but engine start can also be prevented by the immobiliser, in which case you’d find clues in “immobiliser” not “petrol injection”.
When you enter the VIN there are a load of interesting sounding buttons on the left like “physical tests” and “oscilloscope” but the eBay clip tool that I’m using seems to be missing the corresponding required hardware. I’m sure someone who worked in a main dealer 20 years ago will know more

There’s a load of links to documentation too which might be helpful if your installation includes it?