The survey function should be added asap connected to booking a appointment. If you have several qualifying questions in form it can scare leads away from booking since they can see everything they need to fill out at once which leads to them not doing it.

If you fill out a survey with only one easy question per slide then it's easier mentally to fill out and also gives a extra sense of quality than a form does.

If this is hard to do then at least stickiness to a booking form should be added as a fix in the meantime. So you fill out the survey and redirect them to a booking form + calendar where the contact information is already filled out.