see if your current broker will put them on "paper."
They should be able to contact the Transfer Agent (or previous Transfer Agent) and you should be able to get a "paper certificate" of how many shares you owned.
I would "fight" your current broker since you bought shares, and you still own shares.....
Demand to speak to a supervisor, even though you can't trade the shares online, you technically have shares in a "private business" and your shares may be worth something someday.
Dont let them throw your hard earned money away, and document everything just in case (ie. time/date, names of who you talked to, how many shares you own and when purchased). You legally own shares, dont give up!!!!
CBBT CIK Code: CIK 0001453099 (or 1453099)