Sick Chick help

[iron]

Real quick question, quick backstory first. We are new to chickens, we had a broody hen who hatched 4 of her 12 eggs naturally, we incubated the rest. 2 of the 12 hatched, the first was 4 days later than the natural 4, the second was a week after the 4. We put the 2 late comers in with the rest and all appeared good, until last week. The first one of the incubator chicks wasn't acting right, it wasn't associating with the others, it wasn't growing feathers like the rest, it was stumbling and banging its head to the right side (like the scene in the movie "night at the roxbury") it was real lethargic. i separated it and it went down hill fast, to the point it wouldn't stand. I searched all over for a possible problem, after searching and searching the internet, two things came up consistently, Botulism, and Vitamin deficiency. I decided to check for mites or lice, well it was covered in lice.. i believed this to be the issue, along with vitamin deficiency. I dusted the lil guy (lice came running up my arm) and fed it vitamin supplement by syringe.. over night it was standing and appeared to be doing better. By day 2 it was running and trying to escape, drinking and eating tuna mixed with vitamin water. So Sunday i put it in with its siblings and mom all was good except he wasn't joyful and taking part in the activities like the others, he would scratch and eat fine, he would get into the food with the others, he just appeared to be lost.He spent the night under a heat lamp in his cage Sunday night, due to not having a lot of feathers on his back or chest, the feathers he does have look ragged. Yesterday, Monday i had him in with the others most of the day and decided to let him sleep with everyone it was warmer out and I was hoping time with the rest would help him.I checked on him before bed and he was in the nesting box under mom like the rest, i was happy and went to bed... i just checked this morning at 4:30am and found him sleeping alone out in the chicks mini run, while all the others were still tucked in by mom. My question is will he ever be accepted back? I feel so sorry for him, i feel like he's that kid on the playground that just wants a friend... or am i worrying about nothing and he is choosing to be distant? The oldest chicks are almost 5 weeks, so he is about 4 1/2 weeks, the youngest one is doing great. Maybe it's just that he still doesn't feel 100%. any suggestions?