Am I mistaken or is the only way to get the demolition experts into play the boss fight effect?
So if there are no shells on the board none will enter play? Would be a shame. As big a shame as to play the tower with pet parade and name them standard creep and sth else boss creep. Not that a boss creep is needed with the tower, if I'm not overlooking sth.
tdlr is this a case of sloppy design? The ideas look good, the implementation not so much.

It looks like they included creeps with a boss expansion. That's not sloppy. there's no reason they need to be inexorably linked. The next few bosses, at least, will mechanically utilize creeps that come with them, I believe. But this is just two, themed, components in one box.

Might not be, but then it's a missed opportunity

Really, Tetsudo Tower is already very strong. If he was capable of independently generating what are effectively the best models in the game for him to use his ability with, that would be really broken.

I hope to find out soon. He's nearly done being painted. Still, sth would have been nice. Timeout effect seems ideal for this. Maybe I'll houserule it. His actual timeout is probably even stronger, but has less flavour and no creep interactions.

I'll admit being really surprised to discover a boss that literally has minions crawling on his back wasn't able to spawn the creeps that are so closely tailored to him both mechanically and thematically.

Seems like a bit of a blunder to me... meh

I have to admit that testudo is very strong with the experts. This can be countered by the heroes. Otoh he's very tough but not really dangerous without them. So another implementation would have been nice.