... the airport was in a total mess in terms of ATC, standard of the actual airport etc.
Standard for TIP, since 1971, when I started operating there.
how on earth can it be legal to operate into these airports in IMC, so that is my question is it legal to accept these procedures.
Yes, legal....provided you use all due caution.
IE: you cannot expect FRA/LHR/AMS (etc) air traffic control procedures in North Africa...sorry, ain't gonna happen.
NB.
And yes, this very senior Captain still operates to TIP, on occasion.