So I don't curl at the Granite Curling Club but my understanding is that most of the curling happens on the evenings and weekends. For those times, the Curling Club should come to an agreement with Canada Life to use their parking lot, since that parking is always empty on evenings and weekends.
For mornings and afternoons on weekdays, my proposed solution is to increase the parking time limit on Balmoral St between Broadway and Granite Way from 1-hour to 2-hours. I walk down that block of Balmoral St fairly often and there's always lots of parking spaces. The Curling Club could then reserve all of their east parking lot (about 15-20 parking spaces) for seniors/people with mobility issues. Younger people could then park on Balmoral and walk 4-5 minutes, which is inconvenient but shouldn't be a dealbreaker.
It's disappointing to see the Granite Curling Club executives making a bunch of demands from the developer (expanding the east parking lot, revenue sharing, etc.), which is a non-profit organization, instead of trying to proactively solve the parking issues.