We have had times when a single leader managed all the Cubs alone - she set up our current camp placement, where we camp on a site, run by a private adventure company, with proper toilets and sinks available 24hr/day, and THEIR leaders take the Cubs on activities (including bog hopping (which needs old clothes that will get thrown out!), canoeing, wide games, orienteering, archery, climbing wall, crate stacking etc.
So all the leaders need to do is pitch tents, supervise meals (Cubs do some prep and all washup, and we have a great parent who does the shopping and makes a sauce for the dinner), organize campfire, and mind them through the night. We've been going there for almost 15 years now - far more civilized than the Scouts in a farmer's field with a single tap, and using a toilet bucket in a toilet tent that needs to be emptied into a pit and covered twice a day.....nuff said.
There are more of these kind of centres now, and some have hostel beds available onsite (so no need for tents), and some can do meals even if you camp. Depends on what you want to pay for.
If the other leaders don't "do" camping, would they manage hostelling? Then at least there are proper beds and a kitchen. But you can still get out a lot more into the wilds!
Or maybe you could ask your Commissioner, there may be other leaders close enough who would be happy to go and staff a camp with you. I know we always had an extra leader on our Guide camps, as we only had 2 in our pack.
And YYY to communication! We have a meeting with new parents (and any older ones who want to come along) partway through the first session every year. To let them know what's involved, uniform required, our activities, our safety/risk/child protection stuff etc, and also our need for engagement by parents. I have a list there and then for volunteers. And then before Easter (we run Jan-Dec not school year), I put out the main list, where I need 2 parents on shore each week (1 in the Den, 1 on the shore) so leaders can all be on the water with Cubs, a couple of sessions where we need an extra adult for supervision purposes as we're down leaders (usually for training), and hikes (where we invite parents and families to come with us - we often have at least 1 along to enjoy it). And we always put out a call for parents to do a session or part of one if they have skills that would be good to pass on. Or other useful things are the parent who does the shopping, or any parent with a van (to save us hiring one to go on camp), and many cars helping with car pooling to hikes/hostelling trips/camping site etc. We lay it on thick at the start of the year that we need help at times or can't run our programme, and occasionally I have to do that for specific things if there are no offers, but there are a core group who always help out and a few who are rarely/never available (some with good reason - eg. SN DCs and large families in different activities in different directions and health issues themselves - others have never mentioned a reason just not been helpful).