Laundry room headaches

[Supr]

Hi, hoping someone can give me some advice.
Working on my in-laws laundry room. its poured concrete room 9x8. Had a 2" drain put in when the concrete was poured and proper vent through the roof. We're in the process of renovating the room and installing a tankless water heater.
well, we found that the drain for the washer is plugged solid, also the p-trap and connection to the vent stack was done outside of the wall because i'm guessing they didnt want to drill the studs (2x4) for a 2" pipe. The vent and drain are in wall but the P-trap and standpipe are on the outside.
we're trying to fix this all now and do it correctly but not sure how to go about it.
we would like to relocate the washer and we can try to clean out the original drain and re-route the pipe under the concrete. this would be a PITA of course and leave us with out a vent.
we thought about going into an existing drain as there is a bathroom on the other side of the wall. the problem is that the laundry is poured concrete (unknown thickness) and the bathroom is right along the foundation of the house. the current drain was put through the foundation by boring, i dont have a problem doing that but now sure how i would pop it up inside of the laundry room.
i know its complicated but i can put up drawings or pictures if that would help.

easiest thing i could think of doing would be to tap into the existing drain, after cleaning it out, and using a Studor vent.
any ideas? i've tried to describe it as best i could but please let me know if i can clarify.

thank you

 

[Supr]

small update.
this weekend we corrected some gas line issues and installed a tankless heater.
next on the plumbing list will be the washer.
we decided to move the washer to a wall that had a restroom on the other side. this will make it easier for drain and water. only issue i have now is that the water lines are on opposite sides of the vent stack.
i have a Oatey box for the water and drain but would require both hot/cold to be on the same side.
this means i would have to run one of the 1/2" copper water line behind the vent to get it on the other side. its a little close for comfort as the stack is 1.5" going through a 2x4.
i'm sure i'm not the first person to run into this and i'm sure theres an east solution but i'm stumped.

thank you

 

[Sponsor]

 

[Terry]

Pretty much every washer box I've installed was in a 2x4 wall. I normally drill for waste and vents for the far side of the studs and have the water on the side nearest me. The two things pass by each other.

 

[Supr]

thanks terry, much appreciated.
i'm thinking about replacing the rest of the 6-7' iron vent with ABS seeing as the rest of has already been replaced with ABS when it rotted out.
that would probably make it easier to tie in a vent for the washer like i was asking about in the other thread.
was just worried about running copper so close to iron. i've seen copper get rubbed through over man years and dont want that headache.

thanks again.

 

[Supr]

Also, the situation I'm in you can use the picture you posted to imagine what i'm working with.
I have cold water just to the left of the vent and hot water on the right side of that stud between the P trap and vent. I'm trying to install the box in the same place you have it so I'd have to cross the cold water over.
I also have a sink on the other side which is why I was asking about the venting of the washer.

 

[Supr]

well, small update. got the vent installed. ended up just replacing the cast iron with ABS. got the copper tied in and found out i had a bad shut off so replaced that aswell. tried out the system and everything works great.
https://imgur.com/a/MsLhc47