Luka didn't seem to catch onto Tamotsu's tone much. She assumed he was stressed or confused over the revelation that he was alive. It might take a little time, but they'd pick up new leads and eventually find him... They would all be together again.
(Or not! But, c'est la vie. And the mini-arc ends here, I guess.)
A week after Azazel was destroyed, things began to move again for the young Academy students. Hana, Misaki and now miraculously Heise were in the safe hands of the Emiya Family. The Council couldn't touch them, not unless they wanted to march armies and more to the estate gates - and all that would do is harm their reputation and standings with Mages everywhere. For now, they were in the safest place they could be. Heise confirmed that there were other survivors, but he wouldn't reveal any locations even to his half-sisters or the Emiyas. To ensure the survival of the clan, keeping them spread out and hard to detect was the only idea that worked.
After disappearing for that one week, Aegis showed up at the Emiya Estate all of a sudden. He was.. mostly an ally, so he was let in without too much trouble. He entered the infirmary where he expected everyone to still be laying around, but there was nobody there. Only the nurses who directed him to a grand lounge where the students were chilling out. Rico was playing a racing game, crashing into things a lot like you'd expect him to. Misaki was sat on a big sofa watching Rico's game fails between Ryuji and Melissa, enjoying both their company.
"Well, hello..." Aegis said, sounding much brighter than he had before. It was as if he dropped the sour attitude he always carried with him. The icy chill was still there, but he looked and sounded pleased to see the others. "Ryuji, Rico - I'd like a word if you will. In private."
"Hey, stalker!" Misa looked over the back of the sofa at Aegis, smiling and waving before being playfully pulled back down by Meli.