Hi...For practically all RC chargers, the adjusting is planned for packs included similar cells with generally comparable charge state and will not function admirably for your utilization case (distinctive limit cells).

As far as battery holders, most will not fit ensured 18650 cells and I haven't tracked down any great one.

I would either get another charger (for example most Xtar chargers are good and they have exceptionally modest ones) or use something like the TP4056 (USB-fueled board, very modest on eBay) with magnet leads.