Yes, the funds would be aggregated with the individual funds of the purchaser.
The earnest money would be considered an agency account, subject to the guidelines in Sec. 330.7 of the FDIC insurance rules.
The pertinent part reads as follows:
"Accounts held by an agent, nominee, guardian, custodian or conservator.
(a) Agency or nominee accounts. Funds owned by a principal or principals and deposited into one or more deposit accounts in the name of an agent, custodian or nominee, shall be insured to the same extent as if deposited in the name of the principal(s)."