He didn’t say that it wouldn’t affect inflation. He didn’t say it’s value doesn’t go down by printing more. He simply said it’s possible to print an unlimited amount (I assume barring a shortage of paper or ink or labor), and that remains true.

On the other hand, he’s now apparently changed his mind. It would seem he did indeed mean to imply more than just his words.

“infinite” is hyperbole. In this context, it means “more than enough”.

It should be obvious, “infinite” can never apply to real world situations like this.