I have a full charge on the battery. Plenty of cranking amps. The starter is new(out of the box). Could the ignition switch be bad? Wiring appears to be good.
You could have a 1,000,000,000,000,000,000 Amp battery connected to your mower.
If the bloody ground is bad then it still won't crank the engine because the AMPS can not get to the starter.
If you want help, please do what your are asked to do and post the results.
If you want to argue then let me know so I can go help some one who actually wants to be helped, your decision.
You were given 2 test to do back in post # 2 and even the reason for doing them.
We do not need to know if the battery is new, starter is new or your undies are new it makes no difference other than the possibility that you bought a really cheap starter off the web which was cheap because it came from a batch of faulty starters that were supposed to go to landfill.
We need to know if the problem is in the
Battery
Battery leads
Starter
Mower wiring.
The 2 tests that would determine this you were asked to do would have done this and taken about as long to do as your post refuting them.
The No 1 rule when diagnosing a problem is ASSUME NOTHING & SUSPECT EVERYTHING TILL PROVEN OTHERWISE.
In the time I have been running Berts only 2 of the 400 odd cases where a starter had been replaced actually had a faulty starter in the first place.
nearly all of the people who forked out $ 100 to $ 200 Aust were very angry when they realised they wasted all that money and some became quite agressive & abusive .
It is no fun finding out you have been a fool and even worse when you find out you have been an expensive fool.
And to answer your final question, if the solenoid is closing and energising the starter then the only other item which could be faulty is the solenoid.