The matching system has flexibility built into it. Otherwise, it would be difficult to find a match in reasonable amount of time.
Moreover, the match is based on offensive and defensive capabilities. It is possible that your clan could technically be outmatched on defense, but their offensive capabilities (troop levels, army camps) are less.
In my experience, we've actually had pretty good luck with clans that have more TH 10s than us because the bottom half of their TH10s are rushed. Many of them also don't have effective troops nor or are all of their army camps upgraded.
The biggest issue is overcoming the inferno towers, but it isn't insurmountable.



