Photos attached. Is it properly in? Between 10-12 o’clock, it only goes in half that distance. 9 o’lock also kind of works.
I have a wading plug hole too, should I be using that instead?
Wading plug hole only works for timing with manual transmission, as far as I know but could be proved wrong.
Can I suggest, if you remove the rocker cover and slowly rotate the engine in the correct direction, (clockwise looking from the front), until you see the two rocker arms for cylinder #1 at the bottom of the cam, on compression stroke, ( both in and ex valves fully closed), you then can assume the timing TDC pin should be close to where it needs to go in, if all is ok.
IF this process shows the pin a long way from going in then you can safely say your valve timing has slipped, or the belt has jumped or stripped some teeth, (same thing really). You should also at this time , if all is as it should be, be able to, by a slight rotation adjustment, fit the IP timing pin, this should also indicate if the timing belt has let you down.
Failing all the foregoing, remove the harmonic balancer and timing cover and have a good look within. The keyway in the crankshaft nose end should be right at the top, vertically at TDC.
With the timing chest cover removed it will be instantly apparent if any of the timing components have failed.
I'm a bit inclined to think you may have a small "drawback air leak" into your IP, that can cause fuel to drain from the IP fuel gallery via the excess fuel system back to the fuel tank, this can make first time of the morning starting and starting after a prolonged stop difficult. Commonly on manual non EDC pumps that leak occurs at the throttle shaft seal, yours appears to be EDC, I have no experience with that type.