Hi K-Bar,
Yes, you only need to obtain the 24 each category items and build 8 tents, decay of food does not change the amount obtained.
During this process, you can loose 1, 2 or 3 scouts, when only 1 survive 3 more will be sent to you but if you loose all 4 you loose the game.

I found out that as long as I've obtained at least 24 of each categorical items and having 8 tents at some point of the scouting period, my clan will join me, even if some of the said items decay below 24 during this period of game play. Now, my next goal for the next play through is to not lose a single scout.

The clan joins you once you have fulfilled the goals.

Have 8 tents - 24 skins outfits - 24 dry fish - 24 cured meat and 24 bread.

When does the clan join you?

Found a couple more issues and fixed them.
It all looks good now, let me know please if you come upon anything more.
It is a tough start.

Also fixed main goal, seems to work fine now.

Just made small change to scenario, if you happen to loose your 4 scouts, you will get help.
Beware of the lions, keep your scouts close to home.