HACK a POT-LID KNOB COZY
If you have a single heavy sock from an evil washing machine that stole its mate, cut off the toe and slip it over the protruding knob. The knob will hold the sock toe cozy in place during your meal preparation.
No more dealing with the oversize separate pot holder.
There's a couple of things I would try:
1) "Sugru" would probably make a nice finish but I don't know how well it would survive washing-up.
2) Silicone sealant is pretty cheap and would work well - but it will be quite tricky to apply it in a layer all over the knob
Typically these glass lids are mounted with a single bolt through the glass to the knob. I'd unscrew that, remove the knob, and in its place mount a piece of wood with a reasonable shape to use for a knob. So, spherical or cylindrical would be good for a start.
To mount it, I'd pre-drill a small diameter hole and then use a stainless steel wood screw (spax screw; or technically a "cross recess countersunk head spaced thread screw"). Take care to use the original washer that was mounted on the inside, and take care to not create any force on the edges of the hole that goes through the glass – that could make the glass lid break.