This is the correct way to fix.
Weld On Adhesive is called this because it actually "welds" the acrylic. Super glues and silicone don't even come close.
Used to work for a company called Custom Plastic Fabricators, we would make any design out of acrylic. We used different types of the Weld On products, heavy stuff to fill gaps and thin if the parts had a good fit.
If we ran out of the thick for gaps, we would mix up some using little pieces of the acrylic, letting it sit until the acrylic was dissolved into the adhesive.
One thing learned there was when drilling the acrylic or cutting, we would use masking tape on both sides of the plastic to protect it. For drilling we took normal drill bits and re-shaped the drill point to the opposite direction. This stopped the crazing around the hole.
Using any alcohol products to clean causes the acrylic to craze or crack over time. We used MEK to clean the acrylic, this is nasty stuff, you get any in your eyes and it will destroy them fast.
When using the Weld on, the tighter fit the better, we would apply using a plastic bottle that had a small metal straw, letting the adhesive seep into the joint or along the seam needing welded. You can actually see it enter into the seam, this way you can see that it has completely covered the area needing welded. The seam should start looking like a mirror-any bubbles will not look the same.
If the bottle is not available, you can find them at a sporting good store, go to the fishing department and get the little bottles for applying glue when tying "Fly Fishing" hooks.
Worked for this company back in the 1980's, so some lessons have been lost.
Best regards,
Mike Bauer