First of all, apologies for the editing of your reply. Haven't got the hang of the format yet. Only the first line appeared when I clicked reply.Which in no way argues for a reduction of 10,000 in the Roman numbers. Appian also gives Scipio "about 23,00 infantry".
"We" know nothing of the sort; you "know". Suggesting Appian knew so little as to leave out the alae is ludicrous. Appian, like Livy and Polybios, are working from sources, almost all lost to us. These sources all give details, including numbers. It is a matter of choice as Livy (29.25.1-4) makes as plain as the nose on your face (which you ignore to your benefit):
A person minus confirmation bias might note Appian's figures in that lot amongst the others. Note they are not exhaustive. As for Appian's figures, you really can't pick and choose, though you seem wedded to the habit.
The argument from silence. Always looks good. Polybios is lacunose in the extreme regarding Scipio's African campaign. Provide some decent evidence, that is something other than speculation or what you "know" Polybios would definitely have stated when he did not.
You have decided this battle did not take the course the sources have told us. On that basis you now replace source evidence with speculation while dismissing what testimony we have on the basis it does not suit your view. I remain wholly unconvinced.
Second, I could more easily state that this battle never happened. There are no eyewitness accounts and next to no archaeology. The only hard evidence suggests that the stated punitive post battle terms imposed on Carthage were false. I do personally think the battle happened, but no court would uphold my belief.
Not all sources are decent. I have a keen interest in 'King Arthur', and far more has been written on this individual in the c500 years after his 'reign' than on Zama. Polybius and Appian differ greatly on their accounts of the battle, so are clearly using different sources. Appian appears to use Punica for inspiration, a less than reliable account. Appians numbers also appear dodgy, as stated above. That said, he has accidentally stated that 10 legions could have been transported to Africa, when his stated numbers are much lower.
That really only leaves us Polybius, and a figure of 10 legions of foot, is more than probable given the available information imho.