A quick check on tfl.gov.uk suggests a journey time of roughly 84 minutes:
DLR Cutty Sark to Heron Quays = 8
+5 transfer
Jubilee Canary Wharf to Stratford = 10
LOROL Stratford to Camden Road = 20
+12 transfer
Camden Town to High Barnet = 29
This does not allow for waiting time at any location en route. Anything up to 100 minutes should thus be expected.