I am not sure if it works from the UK to Qatar but we have on two occasions sent goods back to the UK as unaccompanied baggage and it was much cheaper than paying excess baggage. The second time it arrived in the UK on the same flight as we did.
It may be worth making enquiries for costs with baggage originating in the UK.
Regarding using the freight allowance for excess (or unaccompanied) baggage, I don't imaging there would be an objection. Check with the employer.