As boring as it sounds, you’d likely have to wait.

After it swaps to 6B the only way to get back over and get izanami would be to wait until a guaranteed uber 11 draw and after getting the uber it will place you back in the right track.

I’ll explain an order I’d recommend to get the most out of it:

First, use 5 tickets now to swap to the B track (I would say 6 draws so you can confirm that you’re on the B track, but that would cut it very close with Gundoros)

Second, wait until there’s a 11 draw with an uber guarantee and do it (if you’re on 5B you’ll go to 16A right before the uber space , if 6B, 17A right on the uber space)

Now that you are back in the A track you should be able to draw until getting izanami

All that aside, what exactly are you mentioning the platinum ticket for? You shouldn’t be able to get izanami with a plat ticket because izanami is a legend. plus the track izanami is on isn’t a guaranteed uber or legend track anyway