No, this has nothing to do with CAIR being an unindicted co-conspirator in the Holy Land Foundation trial.
Instead, CAIR lost its IRS status because they failed to file the require reports:
Donations to the Council on American-Islamic Relations (CAIR) no longer are tax deductible after the organization was among 275,000 tax-exempt organizations purged earlier this month by the Internal Revenue Service.According to the Washington Times, CAIR's membership dropped significantly between 2000 and 2006 from 29,000 members in 2000 to less than 1,700 in 2006, a 90% drop.
The groups failed to file required annual reports, known as form 990s, detailing their revenues and expenses, for three consecutive years. CAIR had been a non-profit on its own, but in 2007, the IRS approved a separate tax-exempt CAIR Foundation. The foundation never filed any subsequent reports. Both the foundation and CAIR national are on the purge list.