Regarding pronunciation: the man says "iras al", the "s" before a vowel keeps the "s" sound just as expected, and doesn't change into a "z" like Portuguese, French and Spanish (some places).
But... He says "ala" instead of "al la", forming a "liaison" between those two "L", meaning an exception of the "bijective" or "one-to-one" correspondence between letters and sounds.
So, is his pronunciation "malbona"?
Well you use, "We go to the park," to say that you go to that park in general but you'd use, "We are going to the park," if your were going to go in the (near) future or if you were on your way already. The meanings are similar but not the same.
"Obviously not the case"? Does Esperanto have different endings depending on tense?
From the tips and notes on "Basics 1": "All present tense verbs end in -as, [...]." Yes, the endings determine the tense. See for example http://esperanto.davidgsimpson.com/eo-verbforms.html for a list of possible conjugations.