Hi - retired TA (male) here :
Yes, as others have said, I wouldn't worry too much at this stage. It could well be his hearing difficulties have - and may still be - undermining his confidence, so that he hardly knows what is expected of him. I'll try to copy a post I have used before that MAY be of some use :
QUOTE :
There used to be a kit of cards and letter blocks called "Soundworks", but it's probably discontinued now.
The theory was that, for some kids, it is easier to SPELL words than READ them, which is a later stage.
It started with three-letter words, with a vowel in the middle - "a" glued onto a board.
The child then looked at the individual letter blocks, and was asked to make the word "c a t". Then ask, how do we change "c a t" into "h a t", which letter do we need to change? Then change "hat" into "ham" (with an emphasis on the "mmmm" sound).
The order sounds were learnt in was similar to today's phonics teaching : s m p t (can't remember them all off hand, but you can look that up on-line.)
This approach was used with our SEN Yr2 children who had been unable to make progress with more conventional methods of learning to read. It is rather time-consuming, and ideally needs resources to be made, but it does work very well.
UNQUOTE
So, if you can find or make suitable letters, and a card with "a" glued in the middle, he may enjoy building the words himself. Use letters that are occurring in words in the books he is bringing home, and go on to make cards for the other vowels if it seems to work with "a".
However, in your case I wouldn't put too much effort in at this stage, particularly if everything else is progressing satisfactorily, but maybe bear it in mind if it seems relevant in the future.