Is Guardian Vigil playable after the block succeeds?

Anarch vampire attempts to block and is successful. Can I play Guardian Vigil before combat?

Name: Guardian Vigil
[AU:C]
Cardtype: Reaction
Discipline: Auspex/Celerity/Fortitude
Requires an anarch. More than one discipline can be used when playing this card. This anarch attempts to block.
[aus] +1 intercept, even if intercept is not yet needed.
[cel] This anarch gets 1 optional maneuver in the resulting combat if he or she blocks.
[for] This anarch does not lock for the block.
Artist: Carmen Cornet

Maybe this thread helps:
www.vekn.net/forum/rules-questions/76321-can-a-vampire-use-multiple-attempt-to-block-effects?start=0

The short answer from that thread is: yes.

i would say that the quoted thread doesn't answer the OP

Once the block is successfull, there is no place for another block attempt

Timo wrote:

i would say that the quoted thread doesn't answer the OP

Once the block is successfull, there is no place for another block attempt

This is exactly the point of confusion for many. A minion attempting to block and a minion who successfully blocks are actually the same thing, per the rulebook glossary definition of "blocking minion." This is what the later pages of the other thread are explaining.

So Guardian Vigil can be played after a successful block, even though the card says "this minion attempts to block." Because, again, per the rulebook glossary, an attempt to block and a successful block are the same. Even though the rest of the rulebook and the actual game mechanics would have one think otherwise (the rulebook does not equate a successful block with an attempt to block anywhere else other than the glossary).