Hi maggieholls. Thanks for the post. I think you may have been given slightly duff information there unfortunately.
As noted, the correct advice is that if you put a reward booking in to a FTV, this FTV will include all the avios, cash, and any vouchers. The FTV can only be used towards a new reward booking, not a revenue booking. When it comes to making a new reward booking both the avios and cash can be used for the avios and taxes/fees/charges required. If there is a 241 included too then this gets put in the FTV for the original voucher owner. With a FTV, nothing gets refunded and it is all on the FTV. The one consistent principle is FTVs resulting from reward bookings can only be used towards making new reward bookings, and FTVs from revenue bookings can only be used for new revenue bookings.