Disability Situation in Ghana: a summary

Our first stop on our world tour is Accra, Ghana.  We leave from Phila on Saturday, Jan. 2 at 6:55 p.m. and arrive in Accra on Sunday at 8:55 p.m. (after an 8-hour layover in London).

Before our departure, we are all asked to research and study the political, geographical and disability systems in the countries we are visiting.  Here is a summary of the Disability Situation in Ghana.

We are staying at the international hostel at the University of Ghana. Here's a map of Accra.

Query for experienced world travellers

Only one month until departure.  I have a question for anyone who has travelled to London and or India.  We have two 8-hour layovers during our trip.  One at Heathrow airport on Jan 3 and one in Delhi on Jan. 23. 

Is is possible for 25 people to see some of London during that time and get back in time for an international flight to Accra? and what about 8 hours in Delhi on Jan. 23 prior to departure for Bangkok?