Is it permissible for someone who arrived in Mecca after ‘Isha’ and did not pray Maghrib, to combine Maghrib and ‘Isha’ with jam‘ taqdim (combining and praying earlier) and qasr (shortening) after the circumambulation, and is his ‘Umrah valid?

"Continuity between tawaf (definition) (circumambulation) and sa'i (the ritual walking between Safa and Marwah) is not a condition. This is the view of Ahmad, Ata, and Al-Hasan (definition), and it was practiced by Al-Qasim and Sa'id ibn Jubair. This is because if continuity is not obligatory within sa'i itself, then it is even less so between sa'i and tawaf. Your 'umrah (definition) is valid, as is shortening the 'Isha prayer if you do not intend to stay for four days or more."