I recon that's it fixed. i would have used K-seal myself but a man can choose whatever poison
one of the few snake oil in a bottle fixes that actually works
drive it for a couple hundred miles then dump the coolant, replace and carry on
crack has probably been there since day 1 and recent work removed the blue devil that was there before.... what would the main dealer do? weeping core plug you say?..... oh we fixed it, come back if it re occurs.
been called an idiot many times, got the badge and certificate, but i run water and k-seal for break in, then dump the lot and fill with coolant. can't say its ever caused a problem
can't say it ever solved a problem...haven't had a coolant leak or gasket problem....
people who do this don't admit to doing this

normally, because you take a kicking from the guy who had to do the job twice or saw a picture on the internet of a totally caked water pump.... its seen as an admission that you don't trust yourself to fit a head gasket properly (MLS gasket)

happy to admit that this isn't my bread and butter job, so i don't necessarily have 100% trust in my ability, Hence i make damn certain i'm not going to have to do it again.
i have not found my engine and radiator internals to be caked up like a motor that has been dosed with 15 bottles by 15 owners and no coolant change for 40 years.
possibly because i use the stuff as intended and follow the instructions
Dave