I have incurred costs by attending the hearing, is it possible to be reimbursed for them?

If you testified at the hearing as a witness, you have the right to reimbursement. This covers both the reimbursement of necessary expenses (e.g. travel costs) and lost wages. The reimbursement must be claimed within 3 days after questioning/hearing took place and the exact amount of reimbursement has to be calculated within 15 days.