Should Lightroom Mobile be renamed Lightroom Crippled?

I frequently photograph for extended periods of time in locations without internet. In an attempt to dump weight from my travel pack, I have purchased an iPad Pro to replace my laptop. The more I find out, the more it appears that Lightroom for iPad is going to make this impossible. I'm hoping that I have just missed something.

I don't need to complete the editing process while I'm away from home. I don't have the time. All I need is the ability to plug an external drive into my iPad Pro and create a temporary catalog that I can import into my master catalog when I return home. This will allow me to check my photos for critical focus, and maybe do a little culling and keywording.  However, it appears that I can't work off of an external drive using Lightroom for iPad. Is this correct? If so, it is a really disappointing limitation.

Let's assume that I'm correct; and that I'm willing to transfer each and every file I want to work with onto the iPad Pro. I'll add keywords, maybe make a few basic edits. But then I need to get these files off of the iPad Pro and back onto external drives WITH EDITS AND METADATA since there isn't an iPad Pro available with enough space to store six weeks of high res RAW files. Is there a way to export the Lightroom for iPad catalog and all images with edits onto an external drive? It doesn't appear so.