Iffy sour

So I made a sour a while back that turned out great. I got about 6Gal from it and still had 1 in a jug. About 2 months ago a took some second runnings and added the 1Gal. I stuck it away in my work room and half forgot about it. I checked on it the other day and the air lock had dried up and there was a thick layer of mold on top which I wasn't super worried about, but I took a sample and had a look under my microscope out of interest and there where bacteria buzzing around in there. After thinking about it, the jug might not of had much alcohol producing yeast in it and since it was fairly low OG to start with could there be something in there that could make people sick? So should I just dump it? One thought I had was to add some beer I had that was less than stella, would the alcohol from that help? Any advice is appreciated.

Did you get an OG reading on the second runnings?

Did you boil the second runnings, or just pitch the other sour in it with no boil?

How much hops did you use in it (assuming you did a boil)?

I didn't but it was second runnings so it'd be fairly low.

As far as I can remember I boiled it with the hops from the first batch. But it's been a while and I'm not 100%. Either way it'd be very low IBU's.

What do you think to adding the other beer? (It's a fairly strong IPA that turned out to sweet)

If it's something you really want to save you could always add more wort/sugar. Considering you added the 1 gallon of original beer, there's probably some yeast still in there. Then, if you're satisfied that it ferments some more, taste it and see if it's worth saving.

If it's been sitting around without a functional airlock and has mold growing all over it I'd be inclined to just toss it though. I may have 10 carboys of sours/all brett beers sitting around at home, but I personally prefer to deal with them in a more controlled manner than this.

You don't think there could be anything harmful in it like botulism? I know Alcohol kills most things, but it's sat for a while with a low ABV. Like I said I'd rather dump it than get sick.

Thanks for the advice BTW.