The IDF says that the Hamas tunnels (they've shown) were located under the "Qatari Building" of the Al-Shifa hospital. Sky News says this is the surgery department of the hospital. Tunnel over-imposed in bright yellow below, in Sky's presentation.
What was Qatar's contribution to this surgery building inside the complex? Did they sponsor or build it, and if so when?
FWTW, Wikipedia claims
In 2013, a special surgical building was opened.
But I don't know if that's the building in question. (Mini-update: it's almost certainly that building: there are photos of it upon completion on sak.ps and one of them shows the bridge connecting it with the ICU, while another has a 2013 timestamp.)
A bit more googling finds a statement from Qatar
[T]HE Chairman of the Qatar Committee for the Reconstruction of Gaza Ambassador Mohammed Al Emadi strongly denounced the Israeli occupations allegations about the presence of a building belonging to Qatar inside the Al Shifa Medical Complex in Gaza, and described them as false allegations aimed at justifying Israels targeting of hospitals as part of its extensive violations that targeted civilians and civilian objects.
His Excellency confirmed in a statement to Qatar News Agency (QNA) that the headquarters of the Qatar Committee, located next to the Port of Gaza, is about three kilometers from Al Shifa Medical Complex [...]
That statement just says the building inside the hospital complex doesn't belong to Qatar and it's not the same as some "the headquarters of the Qatar Committee" (duh) but provides no insight whether Qatar might have sponsored any building inside Al-Shifa in some way.
So, why would the IDF call it the "Qatari Building" still? (FWTW, Haaretz has fully adopted that "Qatari building" terminology in their own map, but still doesn't explain why it's called that.)
FWTW, the internal medicine dept. (mentioned in an answer) is another building, next to it, according to Haaretz.