So if I understand this story correctly, you weren't witholding blocks deliberately you had faulty hardware.
BTCGuild (eleuthria) informed you of this after he noticed what was happening and your hardware was then fixed to work properly
The btc that eligius is witholding is from the period before btcguild when your hardware was faulty.
If this is the case I think he's correct, your hardware would never have solved a block and therefore isn't eligble for pooled rewards.
I have solved my issue at the beginning of the May, then we move to eligius for test, After we see block found by them, we move back to BTCguild.
You can see my block which was mined after May 1st on their list.
Is it clear?
So you are saying that you only mined on eligius AFTER the hardware was fixed, and you were finding blocks and should be paid.
Eligius are saying that you mined with faulty hardware, weren't finding blocks, and therefore shouldn't be paid.
More detailed information would be needed to decide who is right, namely the dates, hashrate, shares and blocks found. GigaVPS has posted some numbers which seem to show that things aren't that bad statistically speaking.