Could I Do Glint's Challenge Alone?

By alone I mean with heroes. :P

It's doable at least in NM -- I did it twice on my ele running a modified discord build + Mhenlo, Lina, Zho, and Herta. Trick is to move your party back & forth between the two entrances. Then at times you will need to flag your mm (and minions) to one side while the rest of the party is on the other side. Towards the later waves I ended up keeping the entire party more nearer to the middle but still guarding both entrances. It really helps to have a high enough Deldrimor rank. The wiki (and its talk page) has more useful tips.

Wow.

NO YOU CAN'T. IT'S IMPOSSIBLE.

Everything's possible.
I h/h this on my imba a lot.
With imba you can camp in the middle and watch how nothing hurts you at all even with enemies in all directions...
After the second wave, I camp the dragon (as enemies don't prioritize it) and let them come at me...

so yes it is doable with heroes.

How?
You didn't ask that question.

Can I ask how!?

I'm confused. O_O

Can you sell your cloths?

And do I sell my destroyer cores? I just salvage them.

Unless you want to use them yourself, both items can be sold to other players.

Cloth of the Brotherhood you can sell to other players, not sure of the price these days (was around 10k last time I checked, but may have dropped or increased since then). It's used to ugrade (the appearance of) your EotN hero armour, which allows you to add that hero to you HoM. If you're wanting to fill your own Hall, keep/use however many you need 1st.

Destroyer Cores are used to make Destroyer Gauntlets, so again, unless you want to make some for yourself, sell them to others (think they maybe go for 250-300gp each, but again I may be way off on the price). There is also an EotN quest that requires 3 Destroyer Cores - up to you of course if you want to complete that one.

Cheers.

For cash, it's much better to salvage cores and sell stacks of granite.

I done it a few times with h/h for HoM then I seen how much better looking the Deldrimor armour was on heroes (imho) and didn't do it again

I hang onto my cores till I get a decent amount for selling, usually for around 300g, occasionaly might find someone desperate for their gauntlets buying for more.

Certainly it's possible. Here's a video from me, showing a possible walkthough. I made it, because I only found "farm Destroyer Cores"-type videos but never videos with the complete mission done the H/H way. The video is cut to the old 15 minute youtube limit (a complete walkthrough is always 20 minutes), so there are certain lag-like jumps. But no hidden magic was cut away, only a few longer fights. It's not a very sophisticated run - I simply killed all that popped up. If you do it more often, you will find better tactics.