Tim told Paige he was going to Seattle, so that is likely the reason he's not in the next episode. He also said the date would be when he gets back, so presumably by next week's episode, the date will not have happened, and may not have even been firmly scheduled.

If the promo actually is of a real kiss - and not just two faces close together - I cannot really imagine Paige going through with the date. Unless Walter takes back the kiss like he did the last time, in which case I honestly couldn't blame her. So Walter....