If you can't have anyone come with you, I would try and set up a video recorder to record your pick ups and drop offs (make sure the date shows up on playback) and a voice recorder (check your state laws) to record the actual meetings.
If she is claiming the child is injured during each visit, see if you can take pictures at the end of each visit to show the child is fine, if the child does get injured make sure you document it.
Keep a journal just for your visits and document everything that way when you take it into court your can say, "jane" fell off her bike and such/such date and scraped her knee and you would have a picture to show.
Keep all other communications written so you have proof of what is discussed.
Good luck
If she is claiming the child is injured during each visit, see if you can take pictures at the end of each visit to show the child is fine, if the child does get injured make sure you document it.
Keep a journal just for your visits and document everything that way when you take it into court your can say, "jane" fell off her bike and such/such date and scraped her knee and you would have a picture to show.
Keep all other communications written so you have proof of what is discussed.
Good luck