Hi there,
In general, the more closely your training matches the requirements of your goal climbs and objectives, the better chance you will have of completing these climbs. The movements of the Killer Core Routine are intended to augment other technical training, they are not a substitute for climbing movement. So it would be ill-advised to completely drop the indoor climbing because climbing is a skill that must be practiced. If you are a beginner, it is a good idea that you continue visiting your local climbing gym. Practicing climbing movement a minimum of 2-3 days/week for an hour or so each of these days will give you a good base.
Uphill Athlete offers 8-week Custom Plans that are tailored to an individual’s personal goals using the resources they have available. One of these custom plans would integrate your time in the climbing gym with other training modalities specific to you.
Hope this helps.