Thoughts on a provider that is well reviewed on TER agreeing to an outcall appointment without needing references or any other screening info other than TER handle ? .......hesitant on keeping appointment , any insights would be helpful

You say she is well reviewed, so I wouldn't worry about it. Also you said she asked for your TER handle. Since you are posting here under alias, we don't know your handle, but if your handle has reviews, and/or whitelists, or if you have a posting history, that might be enough for her. If your handle is not attached to anything then it is a poor form of screening on her part but the risk is more on her than you

She can see that you are active and have reviews/whitelist and that may be enough sometimes.