She doesn't understand the person because when the person feels awkward she ...plays it off/trying to hide it?
ごまかす has a few meanings whether with a malicious or innocent intent. But it essentially means an act to hide the truth. The one in the question is no exception.
Take the following examples.
数字をごまかす would mean to cheat the number like providing a false profit report when the company is losing money
話をごまかす would mean to intentionally not answer a question satisfactorily, to evade the question, or to answer it vaguely, all to let the true answer hidden. Changing the subject is considered the same. It's an act of trying to not talk about the subject.
Below exchange illustrates how one might ごまかす in a casual conversation where A hints to like a girl, B pursues the topic, and A keeps evading. Notice the use of 2 やさしい. 優しい（kind) gets switched to 易しい（easy) with an intention to go off topic.
The sentence in the question follows a similar logic as to why わかんない or hard to understand the other person. Notice how A evades the questions by using related words but going off topic. But he isn't saying No either, just not answering purposefully. That's one way to 話をごまかす.
Below the translation of the above example.