I told my brother that mojo probably came from the Spanish moho. The 'h' in the Chabacano mojo is pronounced by many like the 'h' in English and thus my brother thought that it was spelled as mojo. I have however in the past heard one or two people say this word with a silent 'h' in Chabacano. As you may probably already know, the Spanish 'h' is silent. In this article, I will be spelling this word as mojo.
The Spanish moho means molds and it is the same for the Chabacano mojo, However, some people (like my brother) think that it means 'something spoiled'. This is most probably the result of Chabacano being mainly a spoken language. When enough people say yan mojo ya or even mojo ya ese when talking about spoiled food, more and more people will think that mojo means 'something spoiled'.
I'm not sure if it's grammatically "correct", but the noun mojo in Chabacano, can become a verb by adding tan (present tense) ,yan (past tense), or man (future tense) at the beginning and it will mean molds growing on (something).
Yan mojo= molds grew on (something)
Tan mojo= molds growing on (something)
Man mojo or *ay man mojo= molds growing on (something)
I did a quick survey in the office and asked them how they would spell this word and most said that they would spell it with a 'j and pronounce the 'j' like in Spanish or the equivalent of the English 'h'. It seems clear to most of them though that mojo means molds and not 'something spoiled'.
Other people will spell this word as moho, but this is actually a result of the influence of English; because they will still pronounce the 'h' like in English.
Other words in Chabacano that are spelled with an 'h' in Spanish but are pronounced by many with the English 'h' are the following: almojada/ almujada (almohada in Spanish) and jinca (hincarse in Spanish). I am not sure how this came to be but I don't believe that it is a result of the English influence. I think that it has more to do with how the pronunciation simply evolved.
Santos' Chabacano dictionary lists the word as moho, defined as molds. He also has the word mojoso (note that it's spelled with a j) which he defines as moldy. Camins also lists the word as moho, also defined as molds. With regards to almujada and jinca, Santos spells these words as almujada (with a j) and Hinca/inca. Camins' dictionary doesn't have the word almujada. He spells jinca as hinca.
*in case you were wondering where the Chabacano future tense marker 'ay' went