S3 weak boost????

Abit of help/advice please. I recently had my car stage 2+ mapped at R-TECH, whilst it was there I had the inlet and injectors cleaned and a RS4 FPRV fitted. Upon collection I was advised my car didn't make its potential power as it was running 'weak boost'. My turbo has recently been rebuilt by a reputable turbo specialist near me and he said he would use a 360 deg bearing and a billet wheel for extra reliability. R-TECH blamed my weak boost on the turbo saying it's not very good and is in efficient. Having investigating this a little I found that my throttle body boost hose wasn't seated correctly and after refitting this the car pulled so much better. This would of been a part R-TECH would of removed/refitted so I'm wondering if this could be causing the weak boost and if it's worth getting them to re do the map? Car is currently running 350 bhp and 385 ftlbt. Mods are milltek turbo back decat, new turbo, amd CAI, gfb DV+, RS4 fprv, loba hpfp.
Thanks in advance

To be fair to them they did say they would do it again FOC for me I was just asking if the hose not seating correctly would cause this and if it was worth while redoing it as it's over a hours drive away that's all. One thing to note is that before I had it mapped it would flutter one gear change then when I picked it up I didnt and after reseating the hose it flutters again so it defo sounds like it was slightly leaking boost

thanks for your help

Yeah stock clutch. They said they did a smoke test on it and didn't notice anything but it's going back just for piece of mind now and they said they would prefer it back for their piece of mind too. Faultless customer service to be fair to them

115k clutch feels perfect don't slip at all but it was stage 2 running 320bhp when I bought it so I'm not sure if previous owner as uprated the clutch so I'm gonna run it until it starts slipping