I'm sorry you're having this trouble! I've seen it a number of times. I've seen the tear get worsened when I applied the small patches.

The things that seem to cause/ exacerbate this issue are:

1) Direct sun most of the day.

2) An auto cleaner that climes up into that corner.

3) Floater, tri-chlor feeders that sit in that corner.

4) Fluctuating water height - try your best to keep the water level in the pool ~ consistent, any rise or fall will put more pressure on that area. This includes prohibiting jumping into the pool and especially doing 'cannonballs or jack-knives'.

About your only hope of keeping this liner going until you can replace it next spring is to slap a large enough patch on the corner to be well past the weakened area. Here is some advice on applying a patch.

I'd go at least 2" past any damaged area and perhaps even glue onto the bead. The liner is literally rotting out in that corner and you need to get the patch secured to good liner to have any hope of it holding

If I've been unclear or you want a little more info on what I've said, I'll be back tomorrow or Thursday and will elaborate.