Donatello Trashes Slash
 

In "Donatello Trashes Slash", there is a planet where some creatures who look like Krang live. Their machine makes Slash more intellegent. Maybe they are the Utroms in the 1987 show?

They really don't look like krang or Utroms at all.
We're shown krangs race 2 times in the series first time they look more like Utroms the second time they look like giant lizards.

They evolved into the giant lizards if I remember correctly, as they were clones of Krang. So I always assumed that when they said Krang was banished from his body he looked like that and had his body taken away. But who knows cause like you said in the "Four Musket-turtles" episode it shows them as all looking like Krang.

The series being full of inconsistency makes it hard to pin point. Either way if you consider Krang to be an Utrom then I would go with sure but I don't personally.

But as Putrecent said, those creatures look very little like Krang or a Utrom.