Though the evidence as to whether or not the service record for "Frank Spence" is, or is not Vincent is sketchy there is still evidence that it could be.
The list of
blood relatives gives pause for thought at least, his parents and full blood siblings are all consistent with Vincent's family, his age at attestation etc are all plus points for it being Vincent who had, for whatever reason, signed up with a fictitious name.
But as far as I can see, the jury is still out.
Georgina Birmingham was named, on the register of soldiers effects as n.o.k. and sole legatee
There is a will registered for 'Frank Spence, service no 11713
http://www.rootschat.com/links/01ner/NB: soldiers wills, in my somewhat limited experience, vary from 'I leave everything to xx, signed Fred Bloggs', to more detailed wills which can confirm what you want to know. Unfortunately the only way to find out which sort this one may be is to order a copy (at a cost of £10).
The photo RTL found for a Frank Spence, KOSB, who was wounded and a POW is looking (in my opinion) to be fairly unlikely to be the husband of Vincent's sister, Lily (Orsolina)
I can't see a surviving service record, or pension record for a man of this name and regiment.
There is a medal card for a Frank Spence, KSOB, service no 8619 which indicates he was discharged, Class Z 24.3.19
The POW records (mainly lists with not much info other than name and regiment) show a Francis Spence of KSOB, who was born Wallsend, POW in Germny
https://grandeguerre.icrc.org/en/List/607737/698/4272/and there is a pension record card on Fold3 for a Francis Spence, KSOB service no 8619, discharged 25.3.1919 ( a day out, but who's counting!), living at 76 Sep** St. ,Newcastle - that address is not clear (to me) but can be seen here if anyone has a suggestion, to help check the absent voters registers:
https://www.dropbox.com/s/ciskcbatg3xtcu3/address.jpg?dl=0Says he was born in 1877, was married and had suffered a gunshot wound to his left arm. It states the final pension award was in 1922.
As Orsolina /Lily remarried in 1918, to Robert Guthrie, she either re-married bigamously OR the above Francis Spence was not her husband - I am trying to keep an open mind as anything seems to be possible with this family :-)
Not sure if that is helpful or not :-) This family presents multitudinous problems but, if they were mine, I'd keep everything in the possibles box until and unless I had found some concrete evidence one way or another.
Boo