It may be a little late. But in the future, make sure the cuttings remain in full shade until they have a good number of roots. This goes for all cuttings for any plant.

Like a seed, they're going to take a long time to show significant growth. If you're frustrated, maybe you can ask your friend for more cuttings.

Sometimes they go dormant. Maybe they are putting their effort into the roots. Mine did not grow the first year, but developed roots. This year, it bolted in the spring, & it has gone dormant with the heat. The plant looks good, & will eventually bolt again, but it has not grown for about a month.
They can fruit in pots, but do not over water them. They seem to do best when you neglect them & forget about them for awhile.

If it hasn't rotted, sounds like its putting its effort into developing some roots. I find that once it starts growing, finding it some kind of trellis to climb or hold itself up really helps it take off. Mine are fruiting and blooming now.