Do I need new Yeast? Yeast Starter not working

I made a yeast starter for the first time according to the instructions on this post: https://www.homebrewtalk.com/f39/how-make-yeast-starter-pictorial-76101/. After 24 hours, I see no visible signs of activity and it smells pretty bad; not like beer at all. It smells sort of like rotten cider and a slight vinegar smell. I'm worried the yeast might be bad because when I had it shipped, it was very hot when I took it out of the package since it had been sitting out in the 100+ degree heat for so long.

Should I:
-Order some more yeast and start over
-go ahead and pitch
-Give it some more time before pitching

Thanks in advance for any help.

Trust your nose. You probably got an infection. Bad bacteria reproduce something like 10x faster than yeast. Most of your yeast were probably dead/dormant and got overtaken by baddies.

If you have to have your yeast shipped, maybe dry yeast would survive better.

Just as an aside, most places that ship yeast also sell cold packs for anywhere from $0.50-$1.00 that help maintain cooler temperatures inside the shipped package. Some sites make them easier to find than others. Definitely a good investment if weren't aware of them.

It depends on the yeast you used. Some starters smell bready or yeasty and others smell a little like vinegar. Does it have a layer of white sludge in the bottom? That would be your yeast. If it covers the bottom of your starter flask you have a starter. Decant the beer off the top and pitch the yeasties.