Nice Job on the Doe ..
What I would recommend is getting her out and doing some shooting . Start off with that light load and slowly move up , giving her time to get used to each load . you might just be suprised at the laod she can shoot .She is going to define her range with accuracy and load .

With a 50 cal , a load of 50-65 grains backing a patched round ball will be more then enough and recoil wont be all that heavy unless she is shooting a synthetic or light wood stock . I shoot 80 grains of 3F in my 54 and that does just fine on mule deer and even elk at closer ranges under 50 yards . On mule deer , that charge works fine out to 100 which is my limit when hunting with a muzzleloader , doesn’t mater if im shooting a heavy conical and 110 grains or not .
My wife uses a lighter load in her 50 even for elk . But then we are for the most part in the 25-40 yard range and hunting cows .
Again I would let her decide her acceptable range . Teach her to Hunt . Explain to her why she needs to get within a given range and how that range is going to change as she grows and gains knowledge from practice .
Teach her that passing up a shot isn’t the end of the world ,No shame in it . That it’s the responsible thing to do when it not safe or within her or her chosen weapons range .
spend time now by getting her out and teaching her to stalk and track . if your hunting from standsor blinds . teach her how to pick location , judge distance ....... ther is alot to teach

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