I did a search for you entering: covert mp-e5 trail camera manual. The following came up:
www.trailcampro.com/manuals/2014/manual_mpe5.pdf
There is nothing to show or explain how to view remaining battery strength. My suggestion would be to buy a digital meter and random check your batteries when swapping out the SD card. Digital meters are very handy for doing other electrical tests and are much more accurate than a meter with a sweep hand.
I have been doing this on all my cameras as battery percentage does not tell you much. The reason I say this is: 1)using re chargeable batteries, they never reach 100%. 2)I have been using Duracell Copper Top which test 1.60 volt and Ultimate Lithium which are available up to 9x. The Lithium test 1.79 to 1.83 volt. These are an expensive battery, but last much longer due to higher voltage. They are excellent in cold weather.
Also scrolling down when I did the search, there are various videos on you tube, but any I viewed there was nothing mentioned on viewing battery strength.
Good luck.