I managed it fine, so it's certainly feasible.
The tricky bit is if you have a lot of spawn right inside the door. But I just killed a few critters then ran back out to vet my pets, then we went back in again. Just repeat that until the entrance itself is clear. Then keep that area clear so you always have somewhere safe. Hunt near the entrance till you get more confident, at least if you die at the entrance you can get back to your body more easily
To avoid a lot of spawn in areas like that I set my pet to kill something and call it back to me quickly so it just brings back one or two creatures at a time. Obviously the larger the group you send a pet into, the more spawn it will probably bring back to you. So at first you'd wanna just attack creatures on the outside of the spawn nearest you, calling the pet back really fast. Then gradually take on more as you get used to the spawn.
I start at the entrance and once that's clear it's actually quite straightforward as long as you watch out for new spawn and ensure you move so your pet is between you and the spawn. Otherwise you can end up with the spawn jumping you. Watch out for the liches if I remember right, pretty sure those were doing area effect attacks on me and re-targeting.
The tamer I took in there is a disco/voke tamer but she could handle it fine without the bard skills too, so a range of templates should be ok in there. If you wanted to try some smaller pets in there, I'd recommend using something like a cu or GD to clear the entrance first, then going back for your weaker pets so the spawn isn't all clustered. I suspect the spawn will be a bit tough for many smaller pets though so be very careful.
Wenchy