getting the egg up to searing temps

Is the firebox hole lined up with the vent?

If the Daisy Wheel top off?

Are the holes in the fire grate clear of small peices of lump.

you may actually have OVERFILLED it. or did you light it from the bottom?

you can open the dome if you want to get more air in there. if you have a good fire going, opening it will cause it to fill out all across the top of the lump. i do that when cooking paella, and the fire gets as hot if not hotter than when all vents are open

just shut the dome when you toss the steaks on, and watch for flashback. if you have a lot of fresh lump in there, conditions are ripe for a nice ball of fire when you open it again

I know you're past that problem by now, but I wanted to post some thoughts for future reference.

For high heat, have the bottom vent wide open and the daisy completely off.

The problem you describe is usually attributable to airflow problems. When I hear of people having trouble getting temp past 450 with all the vents open, I have to expect that there's ash (from a previous cook) or dust (added with the new lump) that's blocking the airflow.

Before you cook on or add to old lump, stir it with the ash tool to get the ash to fall through the grate below.

When you're at the bottom of the bag of lump, avoid dumping the charcoal dust into the cooker.

you may also have a slow burning lump that takes longer to get up to temp, and/or your fire starting method was too little, or a bad batch of lump or any combination of everything I have mentioned.

I have had a fire burning for an hour where it still wasn't burning clean and it was just barely to temp, then 5 minutes later the needle on the thermo was pegged and I couldn't get the temp down to where I needed it. (That was funky lump).

Note of caution - using a hairdryer or leaf blower may blow ash around inside your Egg like a snowglobe. This would be ok as long as you don't have food in it at the time.

I have had the best results (for me) starting a fire using the paper towel method and leaving the dome open till after they're gone. whether I need high heat or low, that works the best for me.