Ms Lagwinowicz, and Mr Dmytryszyn, 38, are accused of driving the business analyst's body to a nearby roadside, placing her in the driver seat of her redFord Focus and setting the car alight with petrol.
Ms Lagwinowicz is said to have joined Mr Dmytryszyn in dumping Miss Wells-Burr's body in her redFord Focus before setting fire to the car at about 06:00.