Advice on fixings for heavy vertical radiator

Hi, I've hung an 1800 x 568 vertical rad up in our kitchen ready to be plumbed in. It weighs 48kg dry and sits on 4 metal brackets that have 2 fixing holes each. Afaik the wall is plaster on brick.

The metal nut type fixings I bought initially didn't fit through the bracket holes (the fixings were 8mm diam) so I went with 6x70mm general screws into 10x30mm grey rawlplugs. A couple of the holes I drilled went a little iffy and I don't have 100% confidence in them, so I'm looking to remove the rad and sort them out. This kind of sh*t keeps me up at night as I wouldn't want it to fall off the wall and crush a dog/gerbil/child.

Any advice on the best fixings I should use? And also how to sort out slightly iffy loose holes so that the fixings and brackets are solid?

Something like this or longer...can you drill out the brackets to suit?

https://www.screwfix.com/p/rawlplug-universal-ffi-frame-fixings-10-x-80mm-50-pack/38928

Yes, thanks they look good. I'm guessing 80mm would be more than sufficient when going into a solid wall? Just read in the comments that the screw diameter is 7mm so may not have to drill out the brackets.

Any thoughts on using these filler discs to pack out the couple of iffy holes? https://www.screwfix.com/p/rawlplug-filler-discs-10-pack/642hv

Use resin bonding with wall anchors.

https://www.screwfix.com/p/rawlplug-r-kem-ii-styrene-free-polyester-resin-300ml/32863

(or similar) squirted into the holes before adding plugs will add beef.

Can also support threaded stud without plugs.