How can I get Mass Effect 2 DLC to work for a second Profile?

Question

My Dad has recently been replaying Mass Effect, having brought some DLC for Mass Effect 2 myself I used my profile on his X-Box 360 (using X-Box Live) and re-downloaded the DLC, they are

• Firewalker
• Zaeed
• Normandy Crash Site
• Cerberous Weapons and Armour
• Arc Projector

When I signed out and signed in as my Dad's profile(he doesn't have XBox Live) when I started the game it said the DLC was currupt and it listed all the ones I had downloaded.

So I signed back into my profile, re-downloaded and this time started the game with my account. No message and I got the long wait time after pressing start which I was expecting. I quit the game and signed out and started the game back up in my Dad's profile, I got the same message about the DLC being corrupt.

I repeated the process but before doing the step where I start the game in my Dad's profile I went to Extras -> Downloadable Content to see if the DLC was being registered by the game (I assume it was the long load time which was the sign) however I got a message saying that I had to be connected to the Mass Effect 2 Servers which I never got before. Needless to say when I switched profiles and started the game against I got the same corrupted dlc message.

Now I can not guarantee that the Internet will always be on when my dad plays. Also my dad's profile is set to be the one to auto sign-in on start up since it is his X-Box 360 and I really don't like people going into my profile (it's only on my dad's 360 to download game patches, despite internet connect Black Flag never prompted to update until I started it up in my profile).

I am wondering, how can I get the DLC I brought to be downloaded and working for my dad.

NOTES:

• We are using a physical copy of Mass Effect 2 (dam ass disk swapping)

• The DLC worked fine on my own X-Box 360 console (at least with Mass Effect 2)

• Downloading Mass Effect 2 is out of the question, besides the waste of money my dad only has 3 GB Harddrive (only 2.1 GB free) and i still have yet to download the Mass Effect 3 Extended Ending which is about 1.7 GB

• Letting my dad play my profile is out of the question, I don't want him getting any achievements I haven't gotten

Answer 1

So far the only way around this that I have found is to have your profile signed in, while the other profile (your dad's) plays.

I have achieved this with my profile (XBL) and my housemate's profile (Offline)

• A downloaded version of Skyrim, (Housemate profile signed in, while I played) and the DLC I bought (My profile signed in, while my housemate played)
• Fallout 3 DLC (as above)
• Dark Souls DLC (as above)

Unfortunately I cannot vouch for any achievements you may/may not get while being signed in while another profile is playing. Seeing as it is a Single player game however, your profile should not get any of the achievements your dad gets while he's playing.