If they have to be near one another I'd plump for the lappy bag since the lappy will be turned off completely whilst carrying it about - not on standby or anything able to go in or out of it.
As long as there's a bit of padding between the sections of the bag, eg the part where you stick the mains or 12v lead, plug and transformer is separate from the actual machine with plenty of room for a meter strips and bodger - if the meter case itself is padded enough the contact prongs on the elec plug can't hurt it. I presume you turn your lappy AND your meter off after use, with the on/off switches, rather than using up battery power on either of them to time out?
Interestingly the Insight meter is much the same, especially when plugged in to recharge. So when recharging on the same side table as both our phones in the house immediately next to where we both sit usually. So when my meter is caseless to plug in to recharge overnight it has to be separated from the little stack of two caseless phones. So we either move eg Pete's wallet, a spectacle case or a nearby ashtray (even if people don't smoke, the more presentable sort are kind of ornaments - so useful for used strips and odd little bits of detritus to save you walking into the kitchen with every bit that appears in a day, just empty it once daily.) You obviously don't answer the phone or make a call in the 60 seconds it takes to test blood and do calculations. At work - it went in my top drawer and my phone in my handbag on the floor in the kneehole under my desk. Grief - first one I ever had in 2007 when they came to our D clinic they cost the NHS over £54 each - and no computer equipment or phone will ever take priority over my LIFE. So - you just have to find a way, and that's that mate.
My handbag still contains my life - money, cards, any paperwork I need that day personally, tissues, lip balm - small mirror, comb - even evening bags always had to be big enough to contain a packet of 20 fags, lighter and the car keys in addition to my cut down detritus, ever since some date in 1997 before I was diabetic! (they all spoil the line of a formal man's jacket) The first meters for personal use were like the size of a shortened and thinned housebrick so they're absolutely tiny now in comparison and nowhere near the onus they used to be.