Hi,

It is not a crack that will spread, it is a butted seam that has been bent by the impact.

That part of the wheel was clearly never part of the way the rims are joined and
it is impossible to say the effect of the impact on the joint proper, from those pics.

Personally I'd bash it back into shape as best as I could, use some metal filler
and file that general area back into shape. It either will be fine as the joint
proper is still fine, or won't won't work as the joint proper is damaged.

They look like quality rims with plenty of wear left in them. My best guess is the
joint proper has survived and you are looking at effectively cosmetic damage.

Of course the safest option is to replace, but I wouldn't unless I thought
the proper joint of the rim has been dangerously comprised in some way.

I can't see any catastrophic failure mode, I'd carry on using it.

rgds, sreten.