I think a whistle and LEDlight would be a great place to start. the CMG/gerber lights are durable and on sale at sierratradingpost.com for $12 . They run on a single AA battery for ease of replacement.

I would worry about knives being too heavy to wear around the neck comfortably. I am sure you know the maturity level of your volunteers and whether they will be able to handle sharp pointy objects, since they may not have a lot of experience doing so.

Since you are planning to 'stay in' I question whether fire starting needs to be made available. Particularly since you will be rotating volunteers in and out, will they have time to practice and use the firestarters? Will you be willing to replace them as they are used up?

A flashlight and whistle are easy to use, for the other items I would look at how much time training with those materials you are willing to commit.

Otherwise i would look to accumulate more blankets and food along with a stach of empty 5 gallon buckets & lids for toilet duty.