Confusion about large mertings add on.

I run a support group over Zoom.

Because meetings run two hours, I updated to the Pro plan so as not to be restricted to the 40 minute limit of the free plan.

However attendance has reached 91 and rising all the time.

I need to plan for larger capacity now.

Am I right in saying it will cost just under $50 per month to allow more than 100 participants with "Large Meetings Add On"?

I only need one licence as the support group facilitator, not several.

There's no cheaper way to have more participants than 100 for a single licence?