After all that I've read about this saga. The bottom line is IMO; Never Ever Pay Any Money Up Front To Any WG We will Never know whether they are lying, or telling the truth. As has been said by OP, many WGs come out with sooooo many excuses when they let us down. But IMO Paying Up Front To Any WG Is A Definite No! No!
Paying upfront is a definitely a bad idea.
Two good examples of where you pay upfront, receive a shit service and have vey little recompense are, Royal Mail and train operating companies.
If either of those two bodies only got paid the full amount when the service was delivered as promised you'd soon see their service improve. As it is, they've had your money so you can just fuck off.
I have a guy does a lot of building work for me and we get on well, I pay for the materials, but he never gets a penny until the job's finished and it's all pukka. He never does a half assed job.
Imagine going to Tesco and they say pay for your shopping first and if we haven't got something in stock, tough shit, we'll let you know when we have.