From what I can tell, yes...you need to use both lights for the flytrap. The only ways (from my limited knowledge) to increase the DLI is to increase the light intensity by either a higher-strength light source, a longer photo period, or moving the light source closer to the plant. So, with your current light setup the two ways to increase the DLI is moving the lamp closer or leaving it switched on for a longer time period.
Sorry about the light talk, it overwhelms me, too. But, it's important to get a basic idea of how it works if you'll be using a grow light very much. Growing outdoors under the sun is much simpler (other than battling tree rats and deer!!!
). Going back to increasing your DLI...you could change the timer to 18 hours...according to Curious Plants calculator and chart this would create a DLI of 26.05 at the one-foot height...this DLI is almost in the center of the "good" range.
Btw, my simplistic (my wife does refer to me as being simple-minded
) idea of DLI is the total daily light a plant gets.
As for "light", there is something called the "inverse square law". It basically states that if you move a light twice as far away from an object it reduces the light energy to 1/4 of the previous intensity. But, if you reduce the distance from the light to the object by half, then the light energy increases 4x. So, if you were to move the light closer than 12" (remember not to overheat/burn the plant!) your DLI would increase even more. Try the one-foot height and see how it does. A weak plant that has been light-deprived can't handle suddenly being thrust beneath a really bright light nor set out in full sun. Starting off with the light a bit high for a few days and gradually lowering it might be a good thing to do.
Yeah, Photone uses the "selfie" camera. Hold it facing up towards the light at plant-height and watch the screen. You will want to purchase the "full-spectrum" widget since your light is a white/yellow one. Also, don't forget the paper diffuser to go over the lens...they state to use an odd (to me) weight of paper...I usually cut my diffuser from old envelopes (be sure there's no marking/security-print on the inside.
The timer will make life easier for you and is very configurable. They're durable and mine have lasted for years.