Perfect candidate right there for a #40 tip and pour. The bubbles on that one seam are less detrimental than u think also, but reinforcement can never hurt. Ive put back together and worked with far worse … I did a similar corner job like that also for a friend. Classic “tank was dropped” results. You can make a jig to fix the corner with polypropylene or polyethylene as 40 does not stick to it. I did just that with a cple clamps and filled in a hole the size of a golf ball. Sanded/buffed it back to clear. You can also make ur jig/walls with packing tape and fill in behind to make ur corner whole again. The tape isnt as clean of course but can work in a pinch.
On closer inspection it looks like most of ur corner is still there. If u pour all 3 seams that make the corner on the inside with 40 that tank will still outlive us both. 3/8-1/2” thick pours should do it no problem. Lots of options for fixing/reinforcing it. You can also glue a strip of acrylic on the outside top to bottom of the seam with 1/4” thick acrylic and 40.