When your pen setup is not sufficient to accomodate an unwilling critter, you gotta be smarter than she is and make her think it's her idea to go where you want her to go.
First thing is to keep her from getting spooked if at all possible, so work her with kid gloves... verrry easy!! It may be too late for this already.
Remember, you won't be able to outrun her unless on horseback...and then the horse better be able to jump fences, too.
If she will eat cubes, maybe you can lead her into the pen with a bucket and get your buddy to hide, OUT OF SIGHT somwhere that he can shut the gate once she goes in the pen. If there are other animals in her neighborhood, see if you can entice,with feed, the whole group to come into the pen, drawing her along with them. One person leading with feed bucket, another walking, slowly, behind the group to encourage the spooky ones (her) to stay with the group. Don't push the group too much, they will just booger off. USE your friendly cow...keep the group together... if some split off, JUMPY will certainly join them...then you are messed up... all the gentle stuff is in the pen... the wild stuff is boogered and teaching each other to be even wilder.
Typically, calves stick with their momma... however, if perchance you DO get the calf penned...as a last resort you can leave it in one pen and hope that, give time and the pressure of a taunt bag, the cow will come to the calf (hopefully bawling calf) and enter a pen adjacent to where the calf is. Then, if you can shut the gate, grand. If you only have one pen, rope the calf by those wonderful horns, tie it to the pen fence farthest away from the gate and leave the gate open so the cow will come in. Don't let the cow get next to the calf on the other side of the fence where it is tied. Make a big deal of leaving the area... but remember cows don't count... and leave one of you hidden behind to shut the gate when the cow comes in. It may be midnight before she does it...so, settle in with some OFF for a long wait. Treat your cow like she was a deer... avoid sounds, she MUST not see you waiting for her around the pen... wait until she is well inside the pen before seeking to get it shut... tie a rope to the gate so you can swing it shut from afar,if at all possible.
You can tell that I have only limited experience with these things

.... so I am sure there are other approaches that work very well. Final idea... it may take several days to get her penned up... and, if this doesn't work, there is always lead poisioning. Now, if you don't yet have any FRS radios, it is a good time to get some..for you,your buddy, maybe even a 3rd or 4th . Being able to talk to another person when you are dealing with spooky stuff across distances and when you may not be able to see all that is going on is a big benefit... (gosh, I love telling other folks how to spend their money

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Good luck in getting her in the pen!!