Some more math, hopefully all correct
As the event ends on 2/14 @ 0800 UTC, that is midnight PST on the 13th, so we can safely assume there a 5 more chances to run the tire roadmaps, from today the 9th through the 13th. That means to do them all, you will need 10 keys. There’s 3 more tournaments between now and Wednesday, that’s 3 more keys plus the batteries from the milestones.
Each tournament gives 1182 batteries in milestones, so 3546 from these.
Each run of the roadmaps takes 556 + 1099 batteries, so 1655 per day, to run both roadmaps each day would be 1655 x 5, or 8275 batteries.
Running Crusin map 15 more times would yield 36 x 3 x 5, or 540 tires.
The variable here is how many raids you can do and the average tire drop per raid. 5 seems to be the average from many reports, so 5 x 6, or 30 per can assuming a 100% victory rate. For each 1000 tires, you’ll need ~33 cans.
There’s not alot (or any) headroom without some sort of buy, whether coins or $, and you cannot fail on any map unless you want to raid (or buy) even more. Many also missed the roadmaps last Sunday since less keys were given due to war.
Good luck all!