Identifying a misterious yeast

hey, everyone! Last night I brought some beers home. There's an Stout in that lot that has quite a bit of yeast sediment and I'm thinking about culturing it since I only have access to a small selection of dried yeasts (a few from fermentis & notty from danstar).

The beer is good, 'Chocolate Stout' by a mexican craft brewery named 'Cerveceria Jack'. Now, the brewery doesn't have a website and the bottle's label doesn't include info as to what yeast strain it might be.

Is there anyway I can identify the yeast? The chocolate infused to the beer makes it quite hard to detect any other particular flavor in it but I'm thinking an established craft brewery has a better shot at getting an actual Irish/English (other than notty) yeast, would it be worth a shot culturing this yeast? And in if I successfully culture said yeast, any idea how many times could I reuse it to brew stouts?

A million thanks in advance

FYI some commercial breweries use one yeast for primary fermentation, then frilter out and use a different strain for bottle conditioning. Not sure why.

Oh, didn't think about that and that could be very well be the case.

I'm gonna try sending an email to the brewers and see if they are willing to share information about their strains.

edit:
That didn't work, guess I'll have to culture it and hope it turns out a proper Irish yeast