Lord no, don't get someone else involved.
That might be why she is so screwed as it is.
Sounds to me like she needs a good going over. And I mean all over.
A leak may be signs of a more serious issue. You did the right thing by cumming to us for advice.
I think she needs a serious valve job.
While your are at it, you'll want to change her oil and really lube that baby up.
This may be a little messy but it works for me..
And it may take more than one attempt until you get it right.
You really need to plug her leak until there is no more oozing out.
Make sure you have the right size plug. Too little is just not going to do anything for her and too big, well it just won't go in.
If you have the wrong size oil plug, you're just not going to do it right and she won't be happy. Then she will have to go somewhere else to see if someone else can do it right.
Okay, now that you think you have the right size plug, you're going to have to play around with the hole a little to get her all lubed up and ready to receive that plug.
You'll know you've done it wrong when it starts out moaning and purring but then starts getting making this real *****ie and odd sound. When she starts whining and just doesn't feel or sound right, you'll need to stop and start over.
If her valves are knocking then you need to start all over until you do it right. You might need a third person to really make her scream. The best thing about this is you only have to stand back or sit and watch how a real pro does it.
When you're ready to give it another try, you better be sure to wear something to protect you. You want to be sure there are no foreign objects in there and use only new oil, not any that has been used before. Because once you place that plug in and really pumping that oil to her you had better hope you're doing it right and she is happy with it.
If you're doing it right but she starts screaming real loud you are going to have to thrust something in there to make her shut up and not wake up the neighbors. If nothing is oozing out then you know you she likes it. A little drip here in there is nothing to worry about. You might have to clean her up a little and make sure you didn't get any on yourself.
If you continue to have problems then you're not going to be able to ride her. And you definitely don't want to let anyone else on her. That could really mess things up. Especially if they have an accident and and she comes back all banged up. Sure, you can confront the other person about the condition they left her in but hey, they can deny it and it might end up being your problem anyways.
Otherwise, you are just going to wear her engine out and you might as well put her on the curb with a FOR SALE sign her.
As for the problem with your girlfriend, I wouldn't take the advice of anyone here.