What makes you so sure? Just seems pretty baseless to me.
With Roosevelt Franklin and Yip Yip Martians confirmed for as early as wave 2 (in reality), nothing seemed out of reach with this line.
Any major characters missing from the presumed first 5 waves? Something seems to be missing, but I can't quite put my finger on it... Maybe it's just because the humans were such a big part of the show.
He does seem pretty honest, but the things that stick out to me are why wouldn't they just do Bedtime Ernie with wave 1 and Bert with wave 2 instead of the other way around, Waiter Grover coming two waves before regular (but this really means nothing since Super Grover was released before anything), Betty Lou simply being a repaint of Prairie, though he does state variant, Bathtime Bert existing and Alice would seem to be pushing it for a regular figure.
Alright, here were the tentative waves 1-5 for the Palisades SS line (I have never heard waves 3-5 or the exclusives ever discussed anywhere before). This is straight from the horse's mouth from a former Palisades employee, and a special thanks to @muppetspot2 for finding this info.