Hard to see in Technicolor but it looks like plant has lost the growing point.

That happens sometimes. The growing tip dies for no reason on this variety. In a few, one never returns. On most, a new growing tip emerge. On one multiple growing tips merged. This is a Red Robin Tomato.

I've grown hundreds of Red Robin plants and can't remember that happening. However, if I would see a plant like that it would be terminated. MicroTom plants only grow 1/4th the height of Red Robin and they don't start that way either.

Same issue with my Tiny Tim, but look like a new grow tip is coming out though.

This is a line that has a lot of inbreeding. It doesn't seem to cause any problems.

Max, yours is espically weird to me, because all the ones I have had with that leaf don't grow. Anyone have any ideas what causes it? I have seen it passed down from generation to generation.