The job specification identifies a number of skills and will usually weigh some more heavily to emphasize their importance. You must consider if there are minimum skill levels that are essential to the job.
It may be the job is just like many others in your organization, in which case the minimum acceptable skills are likely to have been determined by HR. You should have the opportunity to vary this if you can supply the missing skill in some other way. Perhaps you can restructure the process, deliver some training, or spread the workload over more than one person to give coverage of all the skills.
Be careful with the team-based approach as you don't want to find the only person with a key skill is demanding recompense for their rare skill. It is a matter of degree. Make sure you have a very good reason, such as an outstanding candidate, which you want to include in your team-based approach to get all the skills you need.
Tip
Tip
A business I was working for was rapidly developing its product technology, and to keep pace with the technical demands, I specified a degree-level technical qualification for new recruits. These new employees were some 40 years younger than some of the team who had been doing the job for years, but they were fearful of the new technology's demands. The new graduate staff went through our six month product training program with flying colors. When it came to working with the product and resolving problems, they were completely lost. They did not have the ability to conduct thought experiments and hypothesize what could be wrong. Their problem solving consisted of random acts in the hope of striking it lucky! I specified a training course, to be delivered by our local technical college, to raise their ability to hypothesize experiments and determine results. The existing staff's problem solving skills had been deeply undervalued so was not weighted heavily on the score sheets.
Technology is a leading cause of process change, with a consequent change in the skills needed. You cannot recruit someone to a job "for all time". If you think you can see 5 years into the future and predict what your team will be doing, you are mistaken. Adaptability is an important skill for you and your team. This is why attitude can be more important than aptitude, albeit with a minimum skill capability.
You now have to reach an agreement with the rest of the interview panel.