PC2 e = PC2 with exposure
PC2 E = PC2 'Enhanced'
please, these definitions come from your fantasy! PC2e means PC2 enhanced, as mentioned in the AIR OPS AMC material, PC2E simply does not exist in any OPS regulations.
Exposure is a concept included in PC2 operations and is not defined as you mentioned.
By the way, military ops are far from any PC2e concept that require the same level of safety of PC1 but without the the extra informations such distances and gradients.
Please before teaching, check if you are on the right page.