Pay up + interest
Well he's citing "material adverse effect", which are things that could not be foreseen at the time of writing the purchase contract, that have a material (major) impact.
Bots percentage double checking clearly isn't a surprise item, he could have written it into the contract.
He hasn't shown any of his claims to be material, despite having prompt API access.
He said 100 sample would be enough originally, so the original API limit would have been fine.
He changed his tune to want the API limit removed.
Twitter gave him full API limits promptly after 7 days. 7 days is prompt however much he claims otherwise.
He changed his tune again, to 'failed to raise the limit promptly enough for his liking'.
He has a contract, his whim does not come into it if he did not write that into the contract.
Twitter has been more than generous to him, despite clearly looking for reasons to get an out, they've humored his games anyway.
It's all shit. He clearly wanted to swap some overpriced Tesla stock for overpriced (but more etherial) Twitter stock. At the end of the day Tesla makes and sells cars and will have to compete on multiples that car manufacturers are valued at. If he swapped some Tesla stock for Twitter stock, Twitter could potentially have more upside and so be priced at a higher multiple. He could jump from one overpriced stock, to the next overpriced stock.
But the timing didn't work out and none of it is Twitters problem.
They'll simply add interest to the deal.