The data I have says that if you are training 5 guys together with a level 4 trainer it's basically impossible you are averaging a pop every 3 weeks. MAYBE at 18 if they are all like 5'10'' and have good elastics.... You've listed your best 3, which makes me think you were wprobably single po. and probably level 5 plus trainer on those guys.
Keep in mind that two of the guys (well, three if you count the recently-sold Tuozzi) reached those skills at the end of the season they were 21, while Wray was 20. Newton and Tuozzi were purchased 2/3 of the way through their 18 year old season. Wray was drafted the following season at 18, Menard purchased at 19 yo a month or so later (so he could well have been single-trained previously, but at19 yo + 4 weeks, he was 6-6-7-7-7-5-6 / 1-6-6-5. I had a couple of very low potential guys that got trained slightly the first season, and then a 1k star I picked up after the draft with Wray that got flipped at the end of the year. The following season I drafted a high potential guy and eventually sold him, as I wasn't going to be able to afford a high level trainer in my plan.
I switched over to 1 position (at least for pressure) earlier than I remember too. Of course, other than the allstar SF/SG, they were mostly only being trained every other week - I wanted Namo to try to at least get close to the OD level of the other guys, so I made sure to get him full training and stretch out the other guys.
So, suffice it to say, if you were thinking these guys were 20 and had those skills, I apologize for the lack of clarity. I'm impressed you can read through the wall of text in the first place. ;)
I didn't bother looking up those trainees on your roster page. If those were higher pot. and U20 then those aren't bad at all actually. for star though with OD around that point you are in cap territory. I counted 3~10 more pops for the first guy before he caps. Maybe if you just do ID/IS then he'll be okay, but I think your whole premise was not crosstraining, obviously with 1 RB he is a liability to play at C to say the least!!! This is another factor in the expense of training and why it's hard to make 5 balanced trainees at a time.
May even be less than that - if I were to give them a passing pop, Menard could cap if he was bare minimum star level, and Newton and Wray would be awful close. I had second thoughts about training them much on inside skills when I got my big men trainees - unlike the star guys at guard, I don't want to waste too many weeks with them on two position training skills that can be single position trained. While playing the guys out of position wouldn't be a problem with defensive switches, I decided instead I'll just do 1v1 for forwards and hope for IS pops there, and just accept that I'm not going to improve their ID further. The big guys need more 1v1 to help their guard skills anyhow.